GNOME Bugzilla – Bug 789050
Cloned actors with offscreen effects clipped to source actor
Last modified: 2019-01-24 17:10:09 UTC
Created attachment 361656 [details] [review] possible fix I had created a gnome shell extension to invert the color of windows. A while back a change in how the shell handled display of windows in the workspace ui and app switcher caused the extension to break a bit. The effects are an unpleasant disappearing, flashing and flickering of windows when those elements are active or a window is animated. With the changes made to the shell it seams there is no easy or clean way to fix this from the extension. The cause of the flickering and disappearances is ClutterOffscreenEffect making use of the source actors dimensions instead of the clones and thus rendering into a framebuffer with the wrong offset and size. Attached is a patch to fix this. You can see the issue with the extension, modified with all injection code removed (it still needs to be updated to the new shell versions). https://extensions.gnome.org/extension/1041/invert-window-color/
Work in progress: https://gitlab.gnome.org/GNOME/mutter/merge_requests/52
Also older related reports (duplicates?): https://bugzilla.gnome.org/show_bug.cgi?id=659523 https://bugzilla.gnome.org/show_bug.cgi?id=685766
Fixed with commit 8655bc5d8de6a969e0ca83eff8e450f62d28fbee