Black screen blinking prompt during apt upgrade: what to do?

cross-posted from: https://lemmy.ca/post/1179690

I just did an apt update followed by an apt upgrade, and during the latter the screen went all blank with a blinking prompt. Unresponsive to keyboard and touchpad. I also hear the fans. It's been like this for 10 min now. I think some Nvidia drivers were included in the upgrade. What to do? Is it safe to emergency reboot? I appreciate any suggestions also for post-checks. Cheers!

Update: The suggestion by @nottheengineer@feddit.de worked!