Try these Windows 11 settings first:
- Open Start > Settings > System > Display.
- Under Brightness, set Change brightness based on content to Off.
- This setting can dim or brighten the display depending on what is shown on screen.
- In the same Display area, if available, turn off Change brightness automatically when lighting changes.
- This disables automatic brightness changes based on ambient light.
- If the device supports presence sensing, open Start > Settings > System > Power & battery > Energy recommendations.
- Turn off Automatically dim my screen when I look away.
- This feature is only available on devices with a presence sensor.
If the effect is specifically that background or inactive windows stay dim even after Change brightness based on content is set to Off, check the graphics software on the laptop. A Microsoft Q&A resolution for the same symptom points to graphics power-saving features overriding the Windows setting.
- On Intel graphics, open Intel Graphics Command Center > System > Power and turn off Display Power Saving Technology.
- On AMD graphics, open AMD Radeon Settings/Adrenalin > Preferences > Power and turn off Vari-Bright or similar power-saving brightness features.
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