MPVPaper fix for KDE layer to test

[lx78WyY0J5]

The only thing you can do is select the shell layer with the --layer option.
Your choices are: top, bottom, background and overlay. With background as the default.
In my testing whenever I have those kinds of issues using the bottom layer seems to fix it.
mpvpaper -l bottom ALL video.mp4

Originally posted by @GhostNaN in #111