@mitya57 @muktupavels thanks for reporting back. Directory /var/lib/lightdm was empty in my case:
/var/lib/lightdm# ls -lh #as root user insgesamt 0 Copying /home/<user>/.config/monitors.xml to /var/lib/lightdm/monitors.xml does not fix this issue. -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1665853 Title: Gnome Flashback: Could not assign CRTC to outputs, ignoring configuration To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-flashback/+bug/1665853/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp

