When unplugging my Lenovo Thinkpad T14s laptop from the power adapter, the screen slowly dims. To manually brighten the display on Windows 10, you have to disable Vari-Bright in the AMD Radeon Software settings:
1.Click Start and select AMD Radeon Software.
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2. Select Setting icon located at the top right corner.
3. Select Display tab.
4. Disable Vari-Bright.
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