Using plasma 5.12
The desktop uses “Folder view” layout.
Recently I have begin using a second monitor, so I added another screen with it’s desktop and in the second desktop the default layout is “Desktop Containment”.
When I log out and then lg in, the icons in the screen with the folder view layout are moved away from the places I placed them, but the icons in the screen with the desktop containment layout are kept in place.
So I wanted to change from folder view to desktop containment layout in my first screen, but I desktop properties it appears grayed and I cannot change it.
To do this, I right-click on the desktop and select “Configure Desktop”. ALT-D ALT-S should do the same. And the top item on that screen is “Layout” which I change to “Desktop Containment”.
I have never seen that happen. But then I don’t have two screens. Perhaps there’s a restriction that you can only use a particular layout on one screen at a time.
As it says in the screenshot, »Layout cannot be changed whilst widgets are locked.«
Right-Click at an empty area in the task bar and select »Unlock Widgets«.
Then open your Desktop Folder Settings again. Your layout should be changeable now.
(Edited to add: you can also press Alt+D, L — or select »Unlock Widgets« right in the Desktop’s context menu.)
(Edit #2 I tried a PlasmaShell replacement named »LiquidShell« a while ago; it’s more traditional and barebones. May be worth a look as well.)
I didn’t even think of it because I couldn’t change the layout in the other screen either … but i have just noticed that locking the widgets in one screen also locks them in the other.
Unlocking the widgets it worked.