Not for me (4GB Pi5). I watch a lot of full screen video and Firefox just can’t handle it at all even if it’s the only application running and with only one tab. I tried all the “fixes”. In the end I gave up, tried a few, and settled on Brave, which still gets a bit confused coming out of full screen which “F11 F11 restart” fixes.

I’m still looking forward to the day when I no longer have to execute a child every time I want to do literally anything on Linux.