Hi! This is somewhere between a question and a request.
Since FF 81 it should support VA-API hardware video acceleration on both Wayland and X11:
However, i could not get it to work on Solus with all the required settings:
packages: libva libva-intel-driver about:config: media.ffmpeg.vaapi.enabled=true media.ffvpx.enabled=false gfx.webrender.all=true env: MOZ_X11_EGL=1
Apparently it only works (even on X11) if firefox has been compiled with a wayland-capable GTK+3 (+mesa). I don't know whether that is currently the case in Solus.
Thanks for any ideas or pointers :)