Andrés, indeed upstream language packs are built differently than the Ubuntu locale packages for thunderbird, they don't have the same content, and that's what is causing the problem.
What I haven't managed to understand yet is how/why thunderbird downloaded language packs on upgrade, overriding the ones that are installed system-wide. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1901829 Title: thunderbird fails to open, xml parse error To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/1901829/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs