I recently purchased a Dell P2715Q monitor and it is hooked up to a GeForce GTX 960 using nvidia drivers. If this monitors power turns off, then KDE decides it needs to relayout where everything is. It typically moves the toolbar to the other monitor, but it doesn't draw a wallpaper on the other monitor. I normally just kill plasmashell and reopen it and then it redraws the desktop properly. I have even turned the KScreen service off in System Settings and this still happens.
Steps to Reproduce:
1. Turn off Dell P2715Q monitor
2. Turn on Dell P2715Q monitor
1. All windows and everything repositioned
1. Everything repositioned poorly.
This is just really annoying :)
Thank you for the bug report.
As this report hasn't seen any changes in 5 years or more, we ask if you can please confirm that the issue still persists.
If this bug is no longer persisting or relevant please change the status to resolved.
I can confirm that the problem still exists. In a 2 monitor setup if you power cycle the primary monitor then all the windows on the primary monitor will be shuffled around.
KDE appears to remember which windows belong to the primary monitor, but not their location. As far as I can tell the window sizes are unchanged.
*** This bug has been marked as a duplicate of bug 450068 ***