One of the wallpapers has XFCE on it, but I didn't change my desktop environment. Also of note, when I open the terminal it doesn't look the same as it used to. Instead of the dark purple window it's a black window with white text and the window's icon is a red "X" with a dark blue "T" on it.
This is a headless machine and I connect to it through remote-desktop.
If I go through the applications menu (manually clicking, the super key does nothing and my keyboard does not have a "Fn" key) and go to settings I get the window on the left. Changing the settings in this window does nothing. Right clicking the desktop and clicking "desktop settings" I get the window on the right. This window correctly changes the wallpaper.
When I open the home folder I get Thunar.
My guess is there are two desktop environments competing or something right now? How can I fix this?
Also, weirdly, if I click my name in the upper right I can "lock screen" and "log out..." but I can't "switch user," "suspend," or "shut down."
Thank you in advance for any help.
I guess it switched desktop environments on you? If you're logged out there's supposed to be a way you can switch between desktop environments. It makes sense that the GNOME Settings app would only change wallpaper settings for GNOME, which I think is the main Ubuntu desktop environment. Are you sure you didn't upgrade to a version of Ubuntu that uses XFCE instead of GNOME?
This machine has always been GNOME. I ran "sudo do-release-upgrade." I didn't specify any flags for XFCE. I'm going to try to log in locally and see how it looks there.