Dear KDE veterans,

I have been using Kubuntu for quite some time and yesterday I stumbled across the possibly most disruptive bug so far.
On this machine I have never had any signifcant problems until yesterday, when after about a week of use and regular updates and a scheduled shutdown I only got a black screen with the mouse cursor after the splash screen.

System Information:
OS: Ubuntu 18.04.3 LTS x86_64
Kernel Version: 5.0.0-36-generic
KDE Plasma Version: 5.12.9
KDE Frameworks Version: 5.47.0

Kwin still worked but it was obvious that plasma had crashed since the desktop was not visible and no panels came up. Since everything else seemed to work, I tried starting plasmashell from the terminal, which brought up the desktop briefly but returned to a black screen with mouse cursor.
The error message was almost identical to the one posted here.

When plasma caused problems in the past they were usually solved by clearing .cache and clearing some plasma-related files in .config, but after a couple of reboots, the problem persisted. Creating a new user and therefore having a clean home directory did not solve anything, so I figured it had to do something with some packages I must have had installed this week.
I looked through my logs but could not find any new packages that should have caused the crash. Fortunately I found a post on the forum suggesting that print-manager causes the problem. I purged the package and lo and behold, plasmashell did not crash anymore. I can easily replicate the bug by just installing print-manager again.

I cannot think of a reason why print-manager would cause plasma to crash. Any ideas what I could do to get print-manager working again?

Best regards and many thanks!

You should file a bug about this here https://bugs.kde.org/describecomponents ... nt-manager, I doubt this can be solved through the forum.