How can I customize Edge lighting color in Galaxy Note8?

You can customize the color, thickness, and transparency of the edge lighting as you want.

Navigate to Settings → Display → Edge Screen → Enable Edge lighting → Advanced settings → Adjustment → DONE 

Pictorial representation of the above settings are as follows :  

 
1. Launch the Settings app, tap Display. 
 

2. Tap Edge screen.

3. Tap Edge lighting.

 
4. Tap Advanced settings.

 
5. Tap the color picker, select the color you want, and then tap DONE. To adjust the thickness and transparency of the edge lighting, drag the WIDTH and TRANSPARENCY adjustment bar to the left or right.

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