Fullscreen Youtube videos lag (audio fine, video lags) on Firefox 5.0; it never did on the previous version.
While watching Youtube videos in full screen, the video lags/un-syncs from the audio (audio fine, video lags) in the Firefox version 5.0. It never did that the previous version until I updated to 5.0 a few months back.
Alla svar (1)
I was able to help this problem on Windows XP (where I mainly saw it) by disabling hardware acceleration.
Tools > Options > Advanced > General Tab > Uncheck "Use hardware acceleration when available"