I've gone ahead and recreated this bug following the description by adding foomatic-filters to the blacklist. I received the Traceback indicated with the ubuntu-release-upgrader version 0.220.2, but not with 0.220.3. I was using French for my test. Additionally, I did see unicode characters in my /var/log/dist-upgrade/main.log file.
The message included "ERROR Dist-upgrade failed: 'Le paquet << foomatic-fitlers >> est marqué". The Dist-upgrade failure should not appear in /var/log/dist-upgrade/apt.log so I'm not certain what Sebastian was seeing, but I'm going to mark this as verification done.
I've gone ahead and recreated this bug following the description by adding foomatic-filters to the blacklist. I received the Traceback indicated with the ubuntu- release- upgrader version 0.220.2, but not with 0.220.3. I was using French for my test. Additionally, I did see unicode characters in my /var/log/ dist-upgrade/ main.log file.
The message included "ERROR Dist-upgrade failed: 'Le paquet << foomatic-fitlers >> est marqué". The Dist-upgrade failure should not appear in /var/log/ dist-upgrade/ apt.log so I'm not certain what Sebastian was seeing, but I'm going to mark this as verification done.