* Bug 1705286 - Properly detect mips64.
* Bug 1687164 - Introduce NSS_DISABLE_CRYPTO_VSX and disable_crypto_vsx.
* Bug 1698320 - replace __builtin_cpu_supports("vsx") with ppc_crypto_support() for clang.
* Bug 1613235 - Add POWER ChaCha20 stream cipher vector acceleration.
NSS 3.64 shared libraries are backward compatible with all older NSS 3.x shared libraries.
A program linked with older NSS 3.x shared libraries will work with NSS 3.64 shared libraries
without recompiling or relinking. Furthermore, applications that restrict their use of NSS APIs
to the functions listed in NSS Public Functions will remain compatible with future versions
We had to release 3.63.1 on April 6th in order to temporarily suspend a CA change from 3.63
that would have caused a breakage of Firefox 88. (Bug 1703090)