Olivier, this worked for me. The file which was removed was ~/.thunderbird/2nss1yxl.default/extensions/langpack-en- g...@thunderbird.mozilla.org.xpi
Strangely, when I open Add-Ons in the newly-working Thunderbird, I still see English (CA), English (GB) and Français (all marked "Can't be removed"). $ dpkg -l | grep thunderbird thunderbird 1:78.3.2+build1-0ubuntu1 thunderbird-gnome-support 1:78.3.2+build1-0ubuntu1 thunderbird-locale-en 1:78.3.2+build1-0ubuntu1 thunderbird-locale-en-us 1:78.3.2+build1-0ubuntu1 thunderbird-locale-fr 1:78.3.2+build1-0ubuntu1 As for Andrés, it still worked straight after the upgrade to 20.10, and stopped working yesterday. Cheers John -- 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