I managed to fix that by going to the opera:plugins and disabling the "Allow websites to use the Flash plug-in" option. After that opera stopped freezing after exiting fullscren mode on yt.

]]>https://forums.opera.com/topic/32980/opera-stable-60-0-3255-106-freezing-after-exiting-fullscreen-my-fixRSS for NodeSat, 15 Aug 2026 17:04:56 GMTWed, 12 Jun 2019 20:35:38 GMT60