Emacs UI behaves erratically after losing focus on workspace change

[Jerome Abela]

On a fresh Ubuntu installation:
- install emacs
- give emacs the focus with the mouse
- switch to another workspace (Super+PageDown)
- switch back (Super+PageUp)
- change the size of emacs window
Result: most of the areas that are not file content (buttons, menus, split bars) are black and don't react to clicks. No resize, refresh, iconify, or further focus change can get back to normal.

ProblemType: Bug
DistroRelease: Ubuntu 21.04
Package: emacs 1:27.1+1-3ubuntu3
ProcVersionSignature: Ubuntu 5.11.0-37.41-generic 5.11.22
Uname: Linux 5.11.0-37-generic x86_64
ApportVersion: 2.20.11-0ubuntu65.3
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Sat Oct 9 13:08:23 2021
InstallationDate: Installed on 2021-09-23 (15 days ago)
InstallationMedia: Ubuntu 21.04 "Hirsute Hippo" - Release amd64 (20210420)
PackageArchitecture: all
SourcePackage: emacs
UpgradeStatus: No upgrade log present (probably fresh install)

[Jerome Abela (jeromelon)]

While trying to record a screencast, I noticed that it only happens when using 2 screens.