I think non-composited non-fullscreen is handled
I thought that's what overlays are for? (i.e. for the applications that choose to go this route, they create an overlay of the appropriate type and render into their buffer - Wayland doesn't composite that part, just informs the hardware to scanout from the buffer).
Originally Posted by JS987
Basically should work like video overlays, but with any buffer you choose kind of thing.
Here you go - here's the talk about that: