Bug 495005

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SUMMARY
Ever since upgrading from Plasma 6.1 to 6.2, I am unable to login when an external monitor is connected.

STEPS TO REPRODUCE
1. Have external monitor connected on the login screen (SDDM)
2. Try logging in to user
3. 

OBSERVED RESULT
Password box turns grey, but never starts Plasma
(The screen is stuck on SDDM and never transitions to the black background with plasma logo in the center)

EXPECTED RESULT
Plasma starts after trying to log in

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.2.1
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0
Kernel Version: 6.11.3-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 2 × AMD A9-9420e RADEON R5, 5 COMPUTE CORES 2C+3G
Memory: 7.2 GiB of RAM
Graphics Processor: AMD Radeon R5 Graphics
Manufacturer: Dell Inc.
Product Name: Inspiron 3180
System Version: 1.1.0

ADDITIONAL INFORMATION
One workaround is to:
1. Unplug external monitor
2. Run sudo systemctl restart sddm.service from a TTY
3. Login without external monitor connected
4. Plug in external monitor after Plasma starts

Note: possibly related to #467342