The patch from bug 1764558 (https://gitlab.gnome.org/GNOME/mutter/merge_requests/62) is broken, and should be reverted (or fixed). The breakage it introduces is noticeably more severe than the tiny shadow it fixes.
The broken patch resurrects bug 1718238, which was fixed not long before Bionic's release (but then subsequently broken). Details about the bug re-occurring start at comment 17 of that bug. Screenshot in comment 26.
Quick recap:
- Launch Ubuntu's default desktop (on X11).
- Go to GNOME Tweaks -> Top bar -> disable Application Menu.
- Make sure the gnome-icon-theme package isn't installed.
- Start gnome-terminal -> note that it looks as in the aforementioned screenshot.
For some (unknown) reason the removal of the supposedly irrelevant gnome-icon-theme package makes GTK+ place an icon of 48x48 size as _NET_WM_ICON, rather than a 16x16 one as when this package is installed. Mainstream mutter scales this image from 48x48 to 16x16 and then displays it, as desired. The faulty patch removes the code that scales the image, so the 48x48 version shows up where there's only room for 16x16.
ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: mutter 3.28.1-1ubuntu1
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: Unity:Unity7:ubuntu
Date: Thu May 10 23:25:19 2018
InstallationDate: Installed on 2016-11-09 (546 days ago)
InstallationMedia: Ubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.2)
SourcePackage: mutter
UpgradeStatus: Upgraded to bionic on 2018-03-14 (56 days ago)
I'm setting the Importance to Critical according to step 6 of https:/