Listen for changes in settings in the three Settings Tables on Android (Global, Secure and System)
If you don't set the Value the event will trigger on any value.
In the task, the new value for the configured Custom Setting will be available in the %evtprm3 variable
You can get all the info about the change in the task by accessing the %evtprm() array
Example: How to enable Android P’s Dark Theme when Night Light is on