I just had it again, it's very rare.

And it's happened over the last number of Fedora versions (-1 to -n)

If I come back to use my computer and hit a key at exactly the same time

as the screen decides to blank (I don't use screensavers) then the screen

does blank, but no key or mouse activity (I've tried) will cause the

screen to wake up again.  I know the machine is still active because one of

the keystrokes I tried, woke up and started to play a Youtube video that was

paused on one of my browser instances.

So everything is still working, but nothing (I've found) will un-blank the screen.

Idea's anyone?

[It's hard to replicate, but I seem to be able to time it right/wrong

every few months.]