What does this popup mean, "New Location Detected", what application is displaying it? I get this popup on my Macbook Pro High Sierra 10.13.6.

There is no title bar.  When I click on the popup it does not become selected and the "current application" in the Mac menu remains whatever it was.    

How can I tell what application is displaying this popup?   How can I tell what it means?   What is a "location" -- is this a GPS thing, a network thing (wifi?  Bluetooth?), is it from Maps?   Has my Mac discovered new unknown lands and expanded the horizons of mankind?   How am I supposed to know?   What if I Add?  What if I Decline?   What happens in either case?   Am I  like Kyle in Human Centipad?
On my system, I get this too; it is from Jabber.


If I click on the popup, Jabber appeared in the menu bar.  I think Preferences->Locations controls it.