I tested gnome-font-viewer again on the same systems after upgrading to Ubuntu 22.04.1 and haven't been able to replicate the issue yet.
Ubuntu 22.04.1 gnome-font-viewer 41.0-2 -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-font-viewer in Ubuntu. https://bugs.launchpad.net/bugs/1848942 Title: Freeze on opening font viewer Status in gnome-font-viewer package in Ubuntu: Confirmed Bug description: When I open gnome-font-viewer, after few seconds interface freezes and I only can move my cursor. ProblemType: Bug DistroRelease: Ubuntu 19.10 Package: gnome-font-viewer 3.34.0-1 ProcVersionSignature: Ubuntu 5.3.0-18.19-generic 5.3.1 Uname: Linux 5.3.0-18-generic x86_64 ApportVersion: 2.20.11-0ubuntu8 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Sun Oct 20 20:02:24 2019 InstallationDate: Installed on 2019-10-20 (0 days ago) InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=ru_RU.UTF-8 SHELL=/bin/bash SourcePackage: gnome-font-viewer UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-font-viewer/+bug/1848942/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
