I updated my system on Thursday from 16.04 LTS to 18.04 LTS and the upgrade failed because of the dependency mismatch in libmutter-2-0 described in this question. It was in a state where only console login worked.
The next day, an update of libmutter was available, and I installed it with
sudo apt install libmutter-2-0 --reinstall
and afterwards I installed the ubuntu desktop with
sudo apt install ubuntu-desktop
Now I have a seemingly working system, but is it already in a consitent state? Or are there other steps necessary to take to bring it into a consistent state?
EDIT: Output of
sudo apt update and
sudo apt upgrade:
sudo apt update Hit:1 http://de.archive.ubuntu.com/ubuntu bionic InRelease Hit:2 http://de.archive.ubuntu.com/ubuntu bionic-updates InRelease Hit:3 http://de.archive.ubuntu.com/ubuntu bionic-backports InRelease Get:4 http://security.ubuntu.com/ubuntu bionic-security InRelease [83,2 kB] Fetched 83,2 kB in 1s (107 kB/s) Reading package lists... Done Building dependency tree Reading state information... Done 1 package can be upgraded. Run 'apt list --upgradable' to see it. sudo apt upgrade Reading package lists... Done Building dependency tree Reading state information... Done Calculating upgrade... Done The following packages have been kept back: gimp-gmic 0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.