Desktop changes by itself (location of background and applications)
Ever since Monterey the desktop backgrounds change around with screensaver kicking in. Same with the desktops that I left apps in. I make each desktop have a background and then place specific apps like Thunderbird in a specific desktop. When I come back after a screen save kicks in they are moved around.
Coming from Linux and then FreeBSD I never had anything like this happen with the same setup.
I have a MAC Mini M1 with 16G RAM. Two monitors via HDMI and USB. I use five desktops per monitor a total of 10.
Occasionally they are where I left them.
Mac mini, macOS 12.1