Actually the attached monitors.xml.txt suggests the system doesn't have
any saved configurations for using the laptop screen only. It looks like
it only has known configurations that disable the laptop screen.
That sounds like a bug, and to fix it I can only recommend:
1. Delete
Thank you for taking the time to report this bug and helping to make
Ubuntu better. Next time the problem happens please follow these steps:
1. Run these commands:
journalctl -b0 > journal.txt
journalctl -b-1 > prevjournal.txt
and attach the resulting text files here.
2. Look in
