diff --git a/tests/opt-testcases/tls13-compat.sh b/tests/opt-testcases/tls13-compat.sh
index 7b75808..6172120 100755
--- a/tests/opt-testcases/tls13-compat.sh
+++ b/tests/opt-testcases/tls13-compat.sh
@@ -29,9 +29,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -46,9 +47,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -61,9 +63,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -78,9 +81,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -93,9 +97,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -110,9 +115,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -125,9 +131,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -142,9 +149,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -157,9 +165,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -174,9 +183,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -189,9 +199,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -206,9 +217,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -221,9 +233,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -238,9 +251,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -253,9 +267,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -270,9 +285,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -285,9 +301,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -302,9 +319,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -317,9 +335,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -334,9 +353,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -349,9 +369,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -366,9 +387,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -381,9 +403,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -398,9 +421,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -413,9 +437,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -430,9 +455,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -445,9 +471,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -462,9 +489,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -477,9 +505,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -494,9 +523,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -509,10 +539,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -527,10 +558,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -543,10 +575,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -561,10 +594,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -577,10 +611,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -595,10 +630,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -611,10 +647,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -629,10 +666,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -645,10 +683,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_GCM_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_GCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -663,10 +702,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_GCM_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-GCM:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-GCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -679,9 +719,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -696,9 +737,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -711,9 +753,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -728,9 +771,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -743,9 +787,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -760,9 +805,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -775,9 +821,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -792,9 +839,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -807,9 +855,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -824,9 +873,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -839,9 +889,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -856,9 +907,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -871,9 +923,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -888,9 +941,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -903,9 +957,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -920,9 +975,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -935,9 +991,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -952,9 +1009,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -967,9 +1025,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -984,9 +1043,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -999,9 +1059,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1016,9 +1077,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp256r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1031,9 +1093,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1048,9 +1111,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp384r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1063,9 +1127,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1080,9 +1145,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp521r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1095,9 +1161,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1112,9 +1179,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x25519,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1127,9 +1195,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1144,9 +1213,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x448,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1159,10 +1229,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp256r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1177,10 +1248,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp256r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP256R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1193,10 +1265,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp384r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1211,10 +1284,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp384r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP384R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1227,10 +1301,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,secp521r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1245,10 +1320,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,secp521r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-SECP521R1:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1261,10 +1337,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x25519,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1279,10 +1356,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x25519,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X25519:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1295,10 +1373,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_256_GCM_SHA384,x448,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_256_GCM_SHA384 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1313,10 +1392,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_256_GCM_SHA384,x448,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-256-GCM:+GROUP-X448:+SHA384:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-256-GCM-SHA384 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1329,9 +1409,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1346,9 +1427,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1361,9 +1443,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1378,9 +1461,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1393,9 +1477,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1410,9 +1495,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1425,9 +1511,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1442,9 +1529,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1457,9 +1545,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1474,9 +1563,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1489,9 +1579,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1506,9 +1597,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1521,9 +1613,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1538,9 +1631,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1553,9 +1647,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1570,9 +1665,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1585,9 +1681,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1602,9 +1699,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1617,9 +1715,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1634,9 +1733,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1649,9 +1749,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1666,9 +1767,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1681,9 +1783,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1698,9 +1801,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1713,9 +1817,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1730,9 +1835,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1745,9 +1851,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1762,9 +1869,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1777,9 +1885,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1794,9 +1903,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1809,10 +1919,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1827,10 +1938,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1843,10 +1955,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1861,10 +1974,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1877,10 +1991,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1895,10 +2010,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1911,10 +2027,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1929,10 +2046,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1945,10 +2063,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_CHACHA20_POLY1305_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_CHACHA20_POLY1305_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1963,10 +2082,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_CHACHA20_POLY1305_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+CHACHA20-POLY1305:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-CHACHA20-POLY1305-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -1979,9 +2099,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -1996,9 +2117,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2011,9 +2133,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2028,9 +2151,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2043,9 +2167,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2060,9 +2185,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2075,9 +2201,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2092,9 +2219,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2107,9 +2235,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2124,9 +2253,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2139,9 +2269,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2156,9 +2287,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2171,9 +2303,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2188,9 +2321,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2203,9 +2337,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2220,9 +2355,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2235,9 +2371,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2252,9 +2389,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2267,9 +2405,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2284,9 +2423,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2299,9 +2439,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2316,9 +2457,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2331,9 +2473,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2348,9 +2491,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2363,9 +2507,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2380,9 +2525,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2395,9 +2541,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2412,9 +2559,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2427,9 +2575,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2444,9 +2593,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2459,10 +2609,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2477,10 +2628,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2493,10 +2645,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2511,10 +2664,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2527,10 +2681,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2545,10 +2700,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2561,10 +2717,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2579,10 +2736,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2595,10 +2753,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2613,10 +2772,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2629,9 +2789,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2646,9 +2807,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2661,9 +2823,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2678,9 +2841,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp384r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2693,9 +2857,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2710,9 +2875,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=secp521r1,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2725,9 +2891,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2742,9 +2909,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x25519,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2757,9 +2925,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp256r1.crt -key data_files/ecdsa_secp256r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp256r1_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2774,9 +2943,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp256r1_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp256r1.crt --x509keyfile data_files/ecdsa_secp256r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp256r1_sha256 curves=x448,secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2789,9 +2959,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2806,9 +2977,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp256r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2821,9 +2993,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2838,9 +3011,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2853,9 +3027,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2870,9 +3045,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=secp521r1,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2885,9 +3061,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2902,9 +3079,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x25519,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2917,9 +3095,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp384r1.crt -key data_files/ecdsa_secp384r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp384r1_sha384 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2934,9 +3113,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp384r1_sha384" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp384r1.crt --x509keyfile data_files/ecdsa_secp384r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP384R1-SHA384:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp384r1_sha384 curves=x448,secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2949,9 +3129,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2966,9 +3147,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp256r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp256r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -2981,9 +3163,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -2998,9 +3181,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp384r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp384r1,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3013,9 +3197,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3030,9 +3215,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp521r1,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3045,9 +3231,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3062,9 +3249,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x25519,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x25519,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3077,9 +3265,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/ecdsa_secp521r1.crt -key data_files/ecdsa_secp521r1.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs ecdsa_secp521r1_sha512 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3094,9 +3283,10 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x448,ecdsa_secp521r1_sha512" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/ecdsa_secp521r1.crt --x509keyfile data_files/ecdsa_secp521r1.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-ECDSA-SECP521R1-SHA512:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca2.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=ecdsa_secp521r1_sha512 curves=x448,secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3109,10 +3299,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3127,10 +3318,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp256r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP256R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp256r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3143,10 +3335,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-384 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3161,10 +3354,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp384r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP384R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp384r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3177,10 +3371,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups P-521 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3195,10 +3390,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,secp521r1,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-SECP521R1:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=secp521r1" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3211,10 +3407,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X25519 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3229,10 +3426,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x25519,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X25519:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x25519" \
          0 \
          -c "HTTP/1.0 200 OK" \
@@ -3245,10 +3443,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->O: TLS_AES_128_CCM_8_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+         "$O_NEXT_SRV_NO_CERT -cert data_files/server2-sha256.crt -key data_files/server2.key -accept $SRV_PORT -ciphersuites TLS_AES_128_CCM_8_SHA256 -sigalgs rsa_pss_rsae_sha256 -groups X448 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 ok" \
@@ -3263,10 +3462,11 @@
 requires_config_enabled MBEDTLS_DEBUG_C
 requires_config_enabled MBEDTLS_SSL_CLI_C
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
 run_test "TLS 1.3 m->G: TLS_AES_128_CCM_8_SHA256,x448,rsa_pss_rsae_sha256" \
-         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+         "$G_NEXT_SRV_NO_CERT --http --disable-client-cert --debug=4 --x509certfile data_files/server2-sha256.crt --x509keyfile data_files/server2.key --priority=NONE:+AEAD:+AES-128-CCM-8:+GROUP-X448:+SHA256:+SIGN-RSA-PSS-RSAE-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
          "$P_CLI server_addr=127.0.0.1 server_port=$SRV_PORT debug_level=4 force_version=tls13 ca_file=data_files/test-ca_cat12.crt force_ciphersuite=TLS1-3-AES-128-CCM-8-SHA256 sig_algs=rsa_pss_rsae_sha256 curves=x448" \
          0 \
          -c "HTTP/1.0 200 OK" \
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 9235be7..eb67a71 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -2725,8 +2725,22 @@
 
 component_test_tls13_experimental () {
     msg "build: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, without padding"
-    scripts/config.pl set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
-    scripts/config.pl set MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 1
+    scripts/config.py set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+    scripts/config.py set MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+    scripts/config.py set MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 1
+    CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
+    make
+    msg "test: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, without padding"
+    make test
+    msg "ssl-opt.sh (TLS 1.3 experimental)"
+    if_build_succeeded tests/ssl-opt.sh
+}
+
+component_test_tls13_experimental_no_compatibility_mode () {
+    msg "build: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, without padding"
+    scripts/config.py set   MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+    scripts/config.py unset MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+    scripts/config.py set   MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 1
     CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
     make
     msg "test: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, without padding"
@@ -2737,8 +2751,9 @@
 
 component_test_tls13_experimental_with_padding () {
     msg "build: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, with padding"
-    scripts/config.pl set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
-    scripts/config.pl set MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16
+    scripts/config.py set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+    scripts/config.py set MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+    scripts/config.py set MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16
     CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
     make
     msg "test: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, with padding"
@@ -2750,6 +2765,7 @@
 component_test_tls13_experimental_with_ecp_restartable () {
     msg "build: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, with ecp_restartable"
     scripts/config.py set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+    scripts/config.py set MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
     scripts/config.py set MBEDTLS_ECP_RESTARTABLE
     CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
     make
@@ -2762,6 +2778,7 @@
 component_test_tls13_experimental_with_everest () {
     msg "build: default config with MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL enabled, with Everest"
     scripts/config.py set MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+    scripts/config.py set MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
     scripts/config.py set MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
     scripts/config.py unset MBEDTLS_ECP_RESTARTABLE
     CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
diff --git a/tests/scripts/generate_tls13_compat_tests.py b/tests/scripts/generate_tls13_compat_tests.py
index 07013ae..0bf8555 100755
--- a/tests/scripts/generate_tls13_compat_tests.py
+++ b/tests/scripts/generate_tls13_compat_tests.py
@@ -138,7 +138,7 @@
                 "-sigalgs {signature_algorithms}".format(
                     signature_algorithms=signature_algorithms),
                 "-groups {named_groups}".format(named_groups=named_groups)]
-        ret += ['-msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache']
+        ret += ['-msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache']
         return ' '.join(ret)
 
     def pre_checks(self):
@@ -221,7 +221,7 @@
         priority_string_list = ['NONE'] + sorted(priority_string_list) + ['VERS-TLS1.3']
 
         priority_string = ':+'.join(priority_string_list)
-        priority_string += ':%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE'
+        priority_string += ':%NO_TICKETS'
         ret += ['--priority={priority_string}'.format(
             priority_string=priority_string)]
         ret = ' '.join(ret)
@@ -272,6 +272,7 @@
         ret = ['requires_config_enabled MBEDTLS_DEBUG_C',
                'requires_config_enabled MBEDTLS_SSL_CLI_C',
                'requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL',
+               'requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE',
                'requires_config_disabled MBEDTLS_USE_PSA_CRYPTO']
         if 'rsa_pss_rsae_sha256' in self._sig_algs:
             ret.append(
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index d5e9e01..c71b436 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -8814,9 +8814,10 @@
 
 requires_openssl_tls1_3
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test    "TLS 1.3: minimal feature sets - openssl" \
-            "$O_NEXT_SRV -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+            "$O_NEXT_SRV -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
             "$P_CLI debug_level=3 min_version=tls13 max_version=tls13" \
             0 \
             -c "tls13 client state: 0"     \
@@ -8843,11 +8844,11 @@
 
 requires_gnutls_tls1_3
 requires_gnutls_next_no_ticket
-requires_gnutls_next_disable_tls13_compat
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test    "TLS 1.3: minimal feature sets - gnutls" \
-            "$G_NEXT_SRV --debug=4 --priority=NORMAL:-VERS-ALL:+VERS-TLS1.3:+CIPHER-ALL:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE --disable-client-cert" \
+            "$G_NEXT_SRV --debug=4 --priority=NORMAL:-VERS-ALL:+VERS-TLS1.3:+CIPHER-ALL:%NO_TICKETS --disable-client-cert" \
             "$P_CLI debug_level=3 min_version=tls13 max_version=tls13" \
             0 \
             -s "SERVER HELLO was queued"   \
@@ -8874,6 +8875,7 @@
             -c "HTTP/1.0 200 OK"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_gnutls_tls1_3
 run_test    "TLS 1.3:Not supported version check:gnutls: srv max TLS 1.0" \
@@ -8886,6 +8888,7 @@
             -C "Protocol is TLSv1.0"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_gnutls_tls1_3
 run_test    "TLS 1.3:Not supported version check:gnutls: srv max TLS 1.1" \
@@ -8898,6 +8901,7 @@
             -C "Protocol is TLSv1.1"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_gnutls_tls1_3
 run_test    "TLS 1.3:Not supported version check:gnutls: srv max TLS 1.2" \
@@ -8910,6 +8914,7 @@
             -C "Protocol is TLSv1.2"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_openssl_next
 run_test    "TLS 1.3:Not supported version check:openssl: srv max TLS 1.0" \
@@ -8922,6 +8927,7 @@
             -C "Protocol  : TLSv1.0"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_openssl_next
 run_test    "TLS 1.3:Not supported version check:openssl: srv max TLS 1.1" \
@@ -8934,6 +8940,7 @@
             -C "Protocol  : TLSv1.1"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 skip_handshake_stage_check
 requires_openssl_next
 run_test    "TLS 1.3:Not supported version check:openssl: srv max TLS 1.2" \
@@ -8947,29 +8954,31 @@
 
 requires_openssl_tls1_3
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test    "TLS 1.3: CertificateRequest check - openssl" \
-            "$O_NEXT_SRV -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache -Verify 10" \
+            "$O_NEXT_SRV -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache -Verify 10" \
             "$P_CLI debug_level=4 force_version=tls13 " \
             1 \
             -c "CertificateRequest not supported"
 
 requires_gnutls_tls1_3
 requires_gnutls_next_no_ticket
-requires_gnutls_next_disable_tls13_compat
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test    "TLS 1.3: CertificateRequest check - gnutls" \
-            "$G_NEXT_SRV --debug=4 --priority=NORMAL:-VERS-ALL:+VERS-TLS1.3:+CIPHER-ALL:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+            "$G_NEXT_SRV --debug=4 --priority=NORMAL:-VERS-ALL:+VERS-TLS1.3:+CIPHER-ALL:%NO_TICKETS" \
             "$P_CLI debug_level=3 min_version=tls13 max_version=tls13" \
             1 \
             -c "CertificateRequest not supported"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 requires_openssl_tls1_3
 run_test    "TLS 1.3: HelloRetryRequest check - openssl" \
-            "$O_NEXT_SRV -ciphersuites TLS_AES_256_GCM_SHA384  -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+            "$O_NEXT_SRV -ciphersuites TLS_AES_256_GCM_SHA384  -sigalgs ecdsa_secp256r1_sha256 -groups P-256 -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
             "$P_CLI debug_level=4 force_version=tls13" \
             1 \
             -c "received HelloRetryRequest message" \
@@ -8978,22 +8987,43 @@
 
 requires_gnutls_tls1_3
 requires_gnutls_next_no_ticket
-requires_gnutls_next_disable_tls13_compat
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
 requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
 run_test    "TLS 1.3: HelloRetryRequest check - gnutls" \
-            "$G_NEXT_SRV -d 4 --priority=NONE:+GROUP-SECP256R1:+AES-256-GCM:+SHA384:+AEAD:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+            "$G_NEXT_SRV -d 4 --priority=NONE:+GROUP-SECP256R1:+AES-256-GCM:+SHA384:+AEAD:+SIGN-ECDSA-SECP256R1-SHA256:+VERS-TLS1.3:%NO_TICKETS" \
             "$P_CLI debug_level=4 force_version=tls13" \
             1 \
             -c "received HelloRetryRequest message" \
             -c "HRR not supported" \
             -c "Last error was: -0x6E00 - SSL - The handshake negotiation failed" \
             -s "HELLO RETRY REQUEST was queued"
+
 for i in $(ls opt-testcases/*.sh)
 do
     . $i
 done
 
+requires_openssl_tls1_3
+requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_disabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
+run_test    "TLS 1.3: client and server do not support middlebox compatibility" \
+            "$O_NEXT_SRV -msg -tls1_3 -no_middlebox -num_tickets 0 -no_resume_ephemeral -no_cache" \
+            "$P_CLI debug_level=3 min_version=tls13 max_version=tls13" \
+            0 \
+            -c "HTTP/1.0 200 ok"
+
+requires_openssl_tls1_3
+requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_disabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+requires_config_disabled MBEDTLS_USE_PSA_CRYPTO
+run_test    "TLS 1.3: client does not support middlebox compatibility but server does" \
+            "$O_NEXT_SRV -msg -tls1_3 -num_tickets 0 -no_resume_ephemeral -no_cache" \
+            "$P_CLI debug_level=3 min_version=tls13 max_version=tls13" \
+            1 \
+            -c "ChangeCipherSpec invalid in TLS 1.3 without compatibility mode"
+
 # Test heap memory usage after handshake
 requires_config_enabled MBEDTLS_MEMORY_DEBUG
 requires_config_enabled MBEDTLS_MEMORY_BUFFER_ALLOC_C