Desktop wallpaper setting does not stay after reboot

[MAYBL8]

I right click on the desktop and click “Configure Desktop and Wallpaper”
Wallpaper type shows “Image”
I change it to “Slideshow”
I click “Apply” and I notice the wallpaper has changed.
I restart the laptop and my setting has gone back to “Image”.

Logout does the same thing.

[MAYBL8]

I think I solved this with help from another forums post:

Edit: Ok, I found the “real” solution. I set the environmental variable “QT_QPA_PLATFORMTHEME=kde” in /etc/environment. For some reason, this screws up the wallpapers and Plasma desktop settings

I had that set also and after removing it and restarting the settings stayed set.