Wayland: Transparent windows are not rendered correctly

[GoaLitiuM]

The transparency effect doesn't seem to be fully working on Wayland windows, the window content seems to be smearing when the window is moved around the desktop, looking like it's rendering over itself at the given opacity over and over. This doesn't seem like compositor issue either, as X11 windows are rendered properly transparent with XWayland.

[Kontrabant]

What rendering backend is being used?

e: And I’m presuming that the transparent window flag/property is being set?

[GoaLitiuM]

Vulkan is being used for rendering externally, and yes the transparency flag is set, without it the window looks fully opaque.

[Kontrabant]

This is probably a driver or compositor bug then, as the only possible thing that SDL could be doing wrong is incorrectly setting the window opaque region, which it sounds like it is doing correctly given the behavior you describe when toggling the transparency flag.

[Kontrabant]

I believe that you are using KDE, correct? Can you try this on Gnome to see if there is any difference?