What's this Windows 10 bullseye icon about?

Ever since the Windows 10 1511 update, I'm seeing a new system tray icon. Unfortunately it pops up, then disappears before I can mouse over and click on it to see what it is.

It resembles a small bullseye or target. I can't recall ever seeing it before and I'm coming up empty on Google. I'm guessing it's part of Windows 10, but would like to confirm in case it's malware. I've not installed any new applications, just the Windows 10 update.

That's the "Location sensor in use" icon. (See under "Where are the location icons […]".) The actual icon looks like this .

It might be triggered by Maps or Weather apps, or possibly by the "Find my PC" feature in recent builds (it's in Settings next to Update/Recovery).