choppy video playback in Safari in MacOS Monterey
after upgrading to Monterey, YouTube and Facebook videos were choppy although sound was ok
MacBook Air 13″, macOS 12.1
Posted this in case others have the problem - one person solved it by reinstalling Monterey. I went to Safari/Develop/Experimental Features and turned off VP9 - this was suggested on a stream for Big Sur, but it worked for me on Monterey
