How do I adjust screen brightness?

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Tags

1. #system
2. #available
3. #level
4. #screen
5. #settings
6. #slider
7. #panel
8. #using
9. #control
10. #brightness
11. #adjust
12. #click
13. #start
14. #display
15. #windows
16. #change
17. #option
18. #select