I have about 25 extensions (almost all needed) and firefox lags like crazy, it’s like I’m watching the videos at 10 fps. I download chrome to test it out and sure enough it runs as smooth as butter. Any help?
EDIT: It somehow fixed itself after I started using LibreWolf (with the same addons)
I don’t think this is a firefox-specific problem. I use FF on mac and PC and I’ve never had any issue with youtube. I have an m1 macbook air and a PC with a 4690k and a 1080, so lower spec than yours. 25 extensions running probably doesn’t help, but it isn’t just “firefox is slow”.