This is not the best solution, but I'll post it anyway.
Move your
.config
directory to a safe place where you will find.After that, try to login. If it fails, make sure that you move
.Xauthority
out of the way too.
This is how I got it working. If by any chance you want your config back for a specific program, just copy safeplace/.config/your_important_program_here
back to its original place.