"Pull down notification shade, long press the settings gear and it will start spinning. You will get a pop up.
"The settings are located in settings, system, system ui tuner."
I find no such entry in 'settings' for the Samsung S8.
The same is happening on Samsung S8.
Do not disturb turns on arbitrarily.
I can find no setting that would account for this behavior.
It appears to happen most frequently during the night.
It also seems to turn on after the phone reboots. An unwarranted and unacknowledged default?
When I use...