You appear to have the 'oibaf' PPA installed which commonly causes graphics problems, and might be the problem here too.
To remove all doubt, please uninstall that PPA using the 'ppa-purge' tool. Then if you experience any more problems please open a new bugs for them. ** Changed in: gdm3 (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1908717 Title: Black screen with blinking cursor To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1908717/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs