Comment 24 for bug 1766137

I see the same thing as #17 (Andrew). I type in the password correctly each time. I login to a user (successfully, no errors) and then log out. After that, I login as a different user and I get the purple screen without the desktop showing. I typed the correct password. If I switch users leaving the first user still running (instead of logging that user out) the error does not happen. This happens on 3 different PCs that I've updated to 18.04.