Bug 456800

SUMMARY
When using KDE Neon+Plasma on my desktop, and Manjaro with Plasma Mobile on my PinePhone, the desktop background has repeatedly reset to the default wallpaper upon unlock/login. I initially thought this had to do with the wallpaper being stored on an external hard drive that wasn’t always mounted on my PC, but I’ve since moved it to my home folder, and the problem persisted. Once it occurred on my pinephone, I realized this was probably specific to Plasma. Thankfully, it seems to be happening far less often on my desktop now, but I have no idea why.

STEPS TO REPRODUCE
1. Set a custom wallpaper on Plasma Mobile (a photo, for example)
2. Continue normal use of locking and unlocking regularly, shutting down and rebooting occasionally.
3. If that doesn’t trigger it, try a couple forced shutdowns.

OBSERVED RESULT
Eventually, the wallpaper would reset to the default (currently “Safe Landing”).
I think this may have something to do with a graphical reset or plasma restarting, because one time I unexpectedly witnessed the KDE booting screen while unlocking the phone when it was already on, and the wallpaper reset.

EXPECTED RESULT
The wallpaper stays the same unless I change it or delete the file in cache somewhere.

SOFTWARE/OS VERSIONS
Windows: N
macOS: N
Linux/KDE Plasma: Y
(available in About System)
KDE Plasma Version: 5.25.2
KDE Frameworks Version: 5.95.0
Qt Version: 5.15.5

ADDITIONAL INFORMATION
As stated above, it seems to no longer be occurring on my desktop. The phone software is up-to-date.