Titlebar sliding animations are broken
Sliding animations in titlebars are broken, as during the animation:
- the middle of the sliding widgets is visible below the window's drawn rounded corners
- drawn corners are visible in the middle of the titlebar
Here is the widget hierarchy to reproduce it:
GtkStackwith the slide left-right animation
Then just switch between the two header bars in the stack. I did that in GTK+ 3 and I didn't test it yet in GTK+ 4.
The bug was initialy found with libhandy's
HdyLeaflet widget: libhandy#21.