What is this mysterious Google Maps popup? macOS 10.13.3
This window suddenly opened in the foreground.
It is not directly associated with any program, stays open if everything else is closed, can not be selected in any way, can not be moved or anything. At the time of it opening itself I am miles and miles away from the city of Berlin. This is the second time it happened, the last time being weeks ago.
Googling has not turned up any meaningful results. What is this?
Turns out the perpetrator is - for whatever reason f.lux. 
The window is truly a zombie though and even stays unmovable and open if one of the buttons is clicked. Will inform them. 



EDIT 17.02.18:
Here's their answer:

Thanks for your note - we have fixed this but haven't updated everyone yet.

Make sure you have 39.987 (download again) at

https://justgetflux.com/

The location popup says "f.lux" now and explains what it's doing....