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Don't forget: long (more than 5 sec) click or double fingers click to indicator bar will turn system depended autobrightness.
Intent for Tasker (or another similar application):
Type - Broadcast receiver
Name - "rubberbigpepper.DisplayBrightness.SetBrightness"
Integer extra parameter "BrightnessLevel" means which brightness level (from 1 to 100%) to set
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