This morning, I found that my Mac’s screen wouldn’t wake up. The computer runs 24x7, with the screen blanking after a few hours of idle time. Nearly all of the time, I just tap a key on the keyboard to wake the screen when I want to use it.
This morning, that didn’t work. The screen remained asleep. I tried obvious things like hot-plugging the display and hot-plugging the keyboard, but no luck.