I can partly reproduce this from an earlier Virtualbox installation. After update Kubuntu started and plasma-desktop was still installed. kubuntu-desktop was however missing and by installing it a bunch of other packages was reinstalled too. So perhaps the latest plasma removed vital packages.
I can partly reproduce this from an earlier Virtualbox installation. After update Kubuntu started and plasma-desktop was still installed. kubuntu-desktop was however missing and by installing it a bunch of other packages was reinstalled too. So perhaps the latest plasma removed vital packages.