Bug 472204

The switch user action is dangerous and can easily end up with a blocked desktop.

STEPS TO REPRODUCE
1. Log in to plasma via sddm 
2. Press switch user from the kde menu
3. Select the same user and enter the password

OBSERVED RESULT

The system tries to spawn a new session on a new virtual console with the same user as in an existing session. As a result the new session hangs during the startup and the old session locks up.

EXPECTED RESULT

The system should go back to the existing plasma session for the user, because there cannot be more than one plasma session working in parallel for the same user.

Furthermore, the swith user menu should have a "cancel" action.

SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux 
KDE Plasma Version: 5.27.6
KDE Frameworks Version: 5.107.0
Qt Version: 5.15.10
Kernel Version: 6.3.12-1-MANJARO (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-4750HQ CPU @ 2.00GHz
Memory: 15.5 GiB of RAM
Graphics Processor: Mesa Intel® Iris® Pro Graphics P5200
Manufacturer: Notebook
Product Name: W740SU
System Version: Not Applicable