YouTube + random dropped frames

[Agozer]

I haven't had this issue before, but I think I first noticed it after I updated to Firefox 61.

When I'm watching any video on YouTube, generally the video plays just fine, then suddenly, the video freezes in place for around two seconds (sound continues to play just fine) and then resumes. This seems to happen entirely at random, sometimes after 10 minutes, sometimes after 15, sometimes not at all.

I'm using h264ify, uBlock Origin and Google Search link fix. Disabling h264ify doesn't seem to help.

I watch a lot of Let's Plays, so a video ~30 minutes long suffers anywhere from 0 to 2 of these "hitches".

EDIT: I think I should also point out that audio/video never desyncs.

[DanRaisch]

Does the same thing occur if you launch the application in Mozilla Safe Mode? http://kb.mozillazine.org/Safe_mode

[Agozer]

Either I got lucky with safe Mode, or the culprit is Hardware Acceleration. I guess I have to learn how to live without it. Strange, considering that everything worked just fine a few versions ago.