Comment 22 for bug 1698287

In Regards to mpv:
While vaapi has now been enabled please note that in a 'wayland' session mpv will not work properly with vaapi from the nautilus context menu. Only audio will work, no video.

The issue seems to be --player-operation-mode=pseudo-gui
Not sure what you all can do about this..

(- for my ppa users I'll provide a 2nd .desktop that will allow context menu/vaapi/opengl & produce expected results
Likely named mpv wayland-only or thereabouts, basically -

[Desktop Entry]
Type=Application
Name=mpv wayland-only
Icon=/usr/share/icons/hicolor/scalable/apps/mpv.svg
TryExec=/usr/bin/mpv
Exec=mpv --player-operation-mode=cplayer -- %U
Terminal=false
NoDisplay=true
Comment=Only for context menu in wayland session & vaapi
Categories=AudioVideo;Audio;Video;Player;TV;
MimeType=blah, blah,