UPDATE: IT WASN'T THE PUSHED AUTOUPDATE AT ALL. IT TURNS OUT THAT THE ACTUAL PROBLEM WAS ABOUT AN HOUR BEFORE THE PROBLEM I TOLD APT TO INSTALL "FUSE". APPARENTLY IN CURRENT UBUNTU, INSTALLING "FUSE" VIA APT CAUSES THE OPERATING SYSTEM TO COMMIT SUICIDE. THIS IS A KNOWN ISSUE WHICH IS CURRENTLY "UNASSIGNED". THE PROBLEM, AS WELL AS A ONE-LINE FIX THAT WORKED FOR ME, ARE DOCUMENTED HERE https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1717878
MY WRATH IS UNABATED BUT MY STREAM WILL BEGIN IN ABOUT FOUR MINUTES, I GUESS
Like apparently if you install fuse via apt (this is a very normal package, it is required to run appimages for example) your system is now in a zombie state where it will work UNTIL you next enter gdm (for example because the computer went to sleep) at which point the entire GUI part of your computer is permanently dead
Almost as if… installing fuse… lights a fuse!!!
The horror increases:
Ubuntu actually installs Fuse version 3 by default. However, if you already have Fuse version 3 installed, which you do, and you tell it to install "fuse", it will REMOVE fuse version 3 (and in the process uninstall several vital system components) and install fuse version 2 (which doesn't work in its place).
EVEN ON LINUX, THIS IS NOT A GOTCHA THAT USERS SHOULD BE SUBJECT TO WITH NO WARNING THAT THE SYSTEM IS ABOUT TO DO SOMETHING UNUSUAL.
@mcc that bug report claims they were warned?
@falken I did not read the fine print of what it was doing and I do not believe I should have to have. Every time you install something with apt it says "installing these packages, uninstalling these other packages".
@mcc I wonder if the GUI would have better guard rails to protect critical packages