Screen is off but "pulses" about every minute...?

Jul 19, 2018
I recently installed the 10.3 (8.12.27) rom and have noticed that when the screen is off it starts to pulse about every minute.

What I mean is that the sides of the screen light up pink ( like how they do when you open/close the camera ((but those are blue)))

I was thinking maybe it was a notification thing? Instead of using the led light, but I didn't have any notifications...

The only thing I can think of is that I was casting Google Play Music to a speaker and it was somehow reading that as a new notification?

Has anyone else noticed this pulsing while their screen is off?
Sep 24, 2017
I noticed it a moment ago. This happened when I received a notification from Telegram X. The screen did not turn on, but there was a notification sound, a vibration and a pink/purple blink. Probably is not a bug, it is a feature xD