Add Wayland,X,Mir to NotShowIn/OnlyShowIn
Submitted by Jeremy Bicha
Assigned to Hans Petter Jansson
Some apps just don't support Wayland and maybe they shouldn't. (Examples: X configuration utilities or [currently] screencasting apps)
Therefore, maybe there's some use to having something like "GNOME:Wayland" for $XDG_CURRENT_DESKTOP allowing an app to have a .desktop that includes "NotShowIn=Wayland".