Facebook and CloudFlare have put mechanisms in place to serve SHA-1 certificates to old browsers and operating systems that don’t support SHA-2, but are still widely used in some regions of the world. The CA/Browser Forum, a group of certificate authorities and browser makers that sets guidelines for the issuance and use of digital certificates, decided that new certificates should not be issued after Jan. 1, 2016. Some browser makers like Mozilla and Microsoft are considering an even earlier cut-off date.”]