This is very much a bug in nvidia-graphics-drivers-340. One can debate if software-properties should or shouldn't purge (though traditionally, the argument was that silent frontends shouldn't purge because the user hasn't explicitly asked for that), but if a removed package's unpurged conffiles cause the system to misbehave, that package needs to be rethought to avoid that situation.
** Package changed: nvidia-settings (Ubuntu) => nvidia-graphics- drivers-340 (Ubuntu) ** Changed in: nvidia-graphics-drivers-340 (Ubuntu) Status: New => Confirmed -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to nvidia-graphics-drivers-340 in Ubuntu. https://bugs.launchpad.net/bugs/1761593 Title: Uninstall left nouveau blacklisted Status in nvidia-graphics-drivers-340 package in Ubuntu: Confirmed Status in software-properties package in Ubuntu: Confirmed Bug description: Following a successful install and subsequent use of nvidia-340 - uninstallation of nvidia via Additional Drivers led to a reboot to a desktop at 640x480 px. Investigation found an nvidia created file left on the system blacklisting nouveau, deleted file and rebooted to normal desktop. Didn't think about ubuntu-reporting this - can try and replicate and apport-collect if it's of any use. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-340/+bug/1761593/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp