OSINT - Location - Google ID trick

Just finished some HTB OSINT challenge.
You find someone’s location from their gmail address.
Interestingly enough, with a gmail address, you can get a Google ID (for the google ecosystem of apps) then use that to explicitly view all Google Maps reviews posted by that user ID.

Steps:

1. Goto hangouts.google.com
2. In top left search bar, paste in their gmail address
3. Once their gmail pops up in the little reactive results pane, r-click > Inspect.
4. In the Developer pane that opens, look up a few lines for the hovercard-iod value. Copy it, that’s their Google ID.
5. Goto google.com/maps/contrib/TheirGoogleID

Now you have their general location, per the reviews they’ve left at various geographical locations.