I am using Mac OS Sierra 10.12.5 (16F73) and Safari 10.1.1 (12603.2.4).
When I visit youtube most videos play fine. but some videos say
It also quickly bring up a prompt to say "upgrade flash" which leads me to Adobe website.
But wasn't flash totally discontinued on Mac and Safari? if so, why am I being asked to upgrade flash?
I don't want Flash on my machine.
My understanding was that Youtube/Safari should use everything as HTML5 (H264) stuff. Then what's going on?