Comment 16 for bug 1828639

testing procedure:

For each test:
- multipass launch $release -d 10G
- Installed new dpkg from proposed
- Installed ubuntu-desktop
- Ran do-release-upgrade

the individual runs were:
- Installed xenial (1.18.4ubuntu1.6), upgraded to bionic (1.19.0.5ubuntu2.2)
- Installed bionic (1.19.0.5ubuntu2.2), upgraded to disco (1.19.6ubuntu1.1)

I tried upgrading all the way from xenial to eoan, but it broke down after the bionic->disco update which somehow went wrong in lxd snap transition somewhere or something.

disco->eoan WIP