SUMMARY
My laptop is either used on it own or connected to a dock having two monitors connected. When connected to the dock I setup the desktop by setting the desktop folder for each screen and arrange the icons. 
First it should be noted that I cannot use the same folder for both screens, because setting the same folder for the second screen results in empty desktop. I do not know if it is a bug or on purpose, but it required me to make a symbolic link to the desktop folder and use that for the second screen. 
After I have setup the desktop I lock icons. When I  disconnect it from the dock, the desktop sometimes (!) becomes empty. Only reconnecting to the dock or restarting plasmashell gets back the icons, however now the positions of the icons are lost and they are ordered by name. In other cases the desktop is not empty but the icon positions are lost (become ordered by name), and it also happens, that everything is fine but after reconnecting to the dock the icon positions are lost (become ordered by name) on one or both screens. It also happened that the second screen was totally fresh; i.e. default background, default folder, no panel, etc.
It seems that somehow kscreen cannot correctly deal with screen setup changes or plasmashell does not understand what kscreen says and incorrectly restores the desktop. Maybe some setup files should be deleted and recreated, but I do not know which, and nevertheless, this should not happen.
I am happy to do any test, report log, just tell what you need.

STEPS TO REPRODUCE
1. Setup a two screen layout with a dock, position icons on both screens (the desktop folder for the second screen is a symlink to the desktop folder of the first screen, so we have the same icons, but position can be different), add panel setup background
2. Disconnect the dock either with the laptop running or with sent to sleep
3. Check the desktop on the laptop screen
4. Reconnect to the dock

OBSERVED RESULT
The desktop setup is not kept. Sometimes just the icon positions change and they become sorted by name, in other cases no icons are show at all. It is not predictable. Seems that it depends on the moment of disconnection.

EXPECTED RESULT
The desktop setup, icons arrangement should be kept

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: openSUSE Tumbleweed 20221022
KDE Plasma Version:  5.26.1
KDE Frameworks Version: 5.99.0
Qt Version: 5.15.6