This was not publicly known before. To my knowledge this Google trick was first discovered by the researcher Samy Kamkar (https://samy.pl/mapxss https://samy.p

This was not publicly known before. To my knowledge this Google trick was first discovered by the researcher Samy Kamkar (https://samy.pl/mapxss https://samy.pl/mapxss), though the tool no longer works. When the tool used to work, I tested it using my home router address and it accurately located me. Then, I moved to another house, and the location remained being my old home. Then, after a couple of weeks, it got updated. I think in the final product the resulting location is not only based off one WiFi address. It might try to crossvalidate using the multiple addresses you can see.