Black halo around window in overlay
On the laptop Dell Latitude E7250 with Intel Broadwell graphics, using Debian Sid/unstable with GNOME Shell 3.38.0 and Mutter 3.38.0, Linux 5.9-rc6 and Mesa 20.1.9, having an external 4K screen connected over HDMI, and only using that one, the overlay sometimes does not fully render all windows and shows a black halo instead. Please see below, but note, it’s only about the black border of the terminal window on the fourth workspace. The other black areas is what I obfuscated with GIMP.