Global window shadows
There are currently a number of pretty visible issues with window shadows:
- Fullscreen GTK apps have no shadow in the overview
- GTK3 apps have different shadows than GTK4 apps
- Active GTK windows have different shadows than inactive ones in the overview
- Depending on the window size, shadows look very different in the overview
- Qt apps have no shadows anywhere
From a spatial model point of view lighting is a global thing, so ideally all windows should behave the same in this regard:
- In the session, all windows should have the same shadows (modulo active/inactive), regardless of toolkit
- In the overview, all windows should have the same shadows regardless of window size, fullscreen status, or toolkit
It seems to me that a lot of these issues are due to shadows being drawn by the app/toolkit rather than the compositor, which doesn't really match the conceptual model. I'd be interested in discussing moving it to the shell/compositor side and have global lighting/shadows.