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+Changes
+   * Changed the default MBEDTLS_ECP_WINDOW_SIZE from 6 to 2.
+     As tested in issue 6790, the correlation between this define and
+     RSA decryption performance has changed lately due to security fixes.
+     To fix the performance degradation when using default values the
+     window was reduced from 6 to 2, a value that gives the best or close
+     to best results when tested on Cortex-M4 and Intel i7.