Watch Youtube videos with the mpv movie player. This is a very simple process.
This is how to play a Youtube video with mpv. mpv https://www.youtube.com/watch?v=wdjk_W8nTnompv https://www.youtube.com/watch?v=wdjk_W8nTno This is very easy to do, it does not work with private videos, but it is a nice slimline way to play HD videos on your Linux machine.