I think release upgrader settings changed. To do deb2snap transitions first before upgrade happens.
Because during upgrade, packages are inconsistent, and snap hooks must be deffered until they are safe to execute on the system. Note all other deb2snap transitions were always graceful and would attempt transition later if snap configuration fails during upgrade. See old LXD deb2snap .deb logic. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2061918 Title: package thunderbird 2:1snap1-0ubuntu1 failed to install/upgrade: new thunderbird package pre-installation script subprocess returned error exit status 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/2061918/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs