Usually I change the brightness of my laptop with:
Fn + Home / / The end: Increase / decrease screen
and it works well
However, ~ 50% of the time, after a sleep / resume, brightness is stuck at current level and I can no longer adjust it with the Fn+ … keyboard shortcut.
Also, adjusting the brightness slider here has no effect (it generally works!):
The only solution is to restart the computer, and then after this it is possible to change the brightness.
Why did this happened? How to solve this little problem?