Laptop screen blank after login when secondary external monitor is not connected
Ubuntu does not switch back automatically to only monitor present when booting after disconnecting external monitor.
I've experienced this in two laptops: when possible I work with my laptop connected to an external screen via the VGA port. The problem comes when I boot the computer without that secondary screen connected:
* The login screen comes out ok.
* After login the screen goes black, but I can hear the login sound.
* If I hit ctr + alt + backwards-delete and login again **most of the times** it is fixed, but not all.
* If I log in as a different user everything is OK. Then I log in as my user and it works.
Ubuntu should be able to detect automatically that there is no external monitor present and switch to the laptop monitor.