This is a longstanding bug in our font stack. Things can go very bad when a font in use is upgraded.
See for instance https://launchpad.net/bugs/1600160 It's not been noticed more recently because the Ubuntu font hasn't been updated in a while. (And there is no longer an Ubuntu GNOME shipping the Cantarell font by default.) What about this idea for a workaround: have the upgrader temporarily switch the UI font to a font that hasn't been changed since Jammy? ** Changed in: ubuntu-release-upgrader (Ubuntu) Importance: Undecided => Critical -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to ubuntu-meta in Ubuntu. https://bugs.launchpad.net/bugs/2034986 Title: some text became unreadable during a distribution upgrade Status in ubuntu-meta package in Ubuntu: New Status in ubuntu-release-upgrader package in Ubuntu: New Bug description: I was upgrading from Lunar to Mantic the other day and left a couple of applications open during the upgrade process. During the upgrade the text in audacious became unreadable (I'll attach a screenshot) and I seem to recall the title bar of Firefox being unreadable but the contents of web pages still being readable. ProblemType: Bug DistroRelease: Ubuntu 23.10 Package: ubuntu-release-upgrader-core 1:23.10.5 ProcVersionSignature: Ubuntu 6.5.0-4.4-generic 6.5.0 Uname: Linux 6.5.0-4-generic x86_64 NonfreeKernelModules: nvidia_modeset nvidia zfs ApportVersion: 2.27.0-0ubuntu2 Architecture: amd64 CasperMD5CheckResult: unknown CrashDB: ubuntu CurrentDesktop: ubuntu:GNOME Date: Fri Sep 8 15:39:27 2023 InstallationDate: Installed on 2018-08-10 (1855 days ago) InstallationMedia: Ubuntu-Server 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725) PackageArchitecture: all SourcePackage: ubuntu-release-upgrader Symptom: ubuntu-release-upgrader UpgradeStatus: Upgraded to mantic on 2023-09-06 (2 days ago) VarLogDistupgradeAptclonesystemstate.tar.gz: Error: command ['pkexec', 'cat', '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'] failed with exit code 126: Error executing command as another user: Request dismissed VarLogDistupgradeTermlog: mtime.conffile..etc.update-manager.meta-release: 2021-05-27T16:30:16.970490 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-meta/+bug/2034986/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp