Created attachment 160951 [details]
Specially caused error

SUMMARY

When I click on "Shutdown" and "Restart" in kickoff, there is a fair chance that "ksmserver-logout-greeter" will run without focus: runs in the background of other windows, also overlaps its taskbar.

I decided to check in a new user and this problem is also observed. In KDE 5.26.4 (Manjaro, live-cd) this problem is not present. Before 5.27.7 this problem was not present.

It has the characteristics of a heisenbug. But you can call it as follows:
STEPS TO REPRODUCE
1. Create a default panel
2. Delete one widget or more (important, don't close notifications that they have been deleted)
3. Click "shutdown" or "reboot" in kickoff
Probability of causing a bug: above average

OBSERVED RESULT
ksmserver-logout-greeter will run without focus (_NET_WM_STATE_FOCUSED)

EXPECTED RESULT
"ksmserver-logout-greeter" will run with focus (ahead of windows and the taskbar does not overlap it) 

OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.27.7
KDE Frameworks Version: 5.108.0
Qt Version: 5.15.10
Kernel Version: 6.1.44-1-lts (64-bit)
Graphics Platform: X11
Processors: 4 × Intel® Core™ i3-2330M CPU @ 2.20GHz
Memory: 7.7 ГиБ of RAM
Graphics Processor: GeForce GT 520M/PCIe/SSE2
Manufacturer: PEGATRON CORPORATION
Product Name: A24
System Version: 1.0

ADDITIONAL INFORMATION

Also ksmserver-logout-greeter overrides active windows when clicked on the desktop, if you click on an actively running window, ksmserver-logout-greeter will be overridden.

I didn't find this problem on Wayland

Random bug:
https://ibb.co/LSJDYdP
https://ibb.co/BPwN5q4