Support TLS_FALLBACK_SCSV for preventing protocol downgrade attacks
As described in this article:
TLS_FALLBACK_SCSV is an effective remedy for protocol downgrade attacks on TLS. Without it possible MITM can force the server to use weaker protocol version instead of the best supported protocol signaled by the client.
Chrome and Firefox support it on client-side, except Edge and IE, and lot of top web sites support it on server-side as well.
Eric Lawrence commented
Martin Suchan commented
Note according to the author of SSL Pulse survey about 58% sites already support this feature: