Created attachment 2286 [details] Screenshot It seems that ScrolledWindow::edge-overshot keeps always triggered for any scrolled window which does not have a scroll bar (i.e. it's contents is smaller than the window size). If there is a scroll bar it behaves as it should. This problem is most visible with the "Materia" Gnome theme which has strong overshot effects.
I am using Debian 11, Gnome 3.38, Wayland and a HiDpi monitor.
Looks like a wayland and/or gtk3 theme problem. Can you try with X11 and another theme. greybird-pro works well for me.
It always works fine here, using KDE, X11, and a HiDpi monitor.
Created attachment 2288 [details] Screenshot with greybird (increased contrast) No the problem is still there with X11 and greybird, it's just the edge-overshot effect is barely noticable with that theme but the bug is there. It's clearly visible if I increase the contrast of the screenshot in Gimp.
Andrey, What are we meant to see in your latest image?
(In reply to Paul from comment #5) The curved gradients at the bottom of the scrollable windows. They constantly stay visible, that should not be like that. These are the GTK3 effects triggered by bumping into the extreme points of scrollbar. See ScrolledWindow::edge-overshot in the GTK3 documentation for more details. In the "Materia" theme, for example, these are very clearly visible.
OK. I don't see them at all here. Is it a gnome thing?
(In reply to Paul from comment #7) Probably, I use Gnome. But no other program out of dozens that I use displays this behavior. Claws Mail uses some non-standard approach for drawing window contents? Some hacks and tricks?