Mintinstall installer tests:

apt errors:
- select python3 package, should immediately change button to forbidden (can't remove) - no error popup
- select grep, should be forbidden also - no error popup
- select tar, should show try again, popup showing dependency error
- any operation, no network connection, should popup network connection error (network isn't needed to 'show' a package)

flatpak errors:
- disconnect network, select package, should show network connection error (this happens while attempting to resolve the package info).
- select package, start install, disconnect network, should show specific operation error, as well as a network error triggered by
  reloading the package view.