Dear Maintainer,
* What led up to the situation?
Connection of external monitor via HDMI, configure external monitor as primary, disable notebook monitor, close lid.
Use external monitor as primary, suspend and resume works, everything ok.
Disconnect the external monitor with the lid closed, open lid, and now the notebook monitor is black. Not possible
to use the notebook without either reconnecting to external monitor or rebooting notebook.
Not even changing to a TTY shows anything.

* What outcome did you expect instead?
After disconecting external monitor with lid closed, notebook monitor becomes primary and works.