here's what i did some time ago:
-install mplayer, and get it working with the framebuffer (-fbdev or -fbdev2)
-install youtube-dl, which essentially downloads youtube clips
-create a script that will open mplayer for the youtube clip being downloaded on completion
-bind the script to a key in elinks
the last two steps are detailed here: https://www.reddit.com/r/unixporn/co...s_and_mplayer/
getting mplayer working the way you want it to with the framebuffer can be a little tricky, but there are plenty of tutorials out there.
using this method you wouldn't have to worry about using a WM/firefox, and you're still using a browser (just text-based).