After being kneecapped by a #patents troll years ago, #Mozilla Location Services, the only somewhat trusted (non-Google/Apple) "Wi-Fi positioning system" (geolocation based on triangulating collected #WiFi SSIDs), is now shutting down: https://github.com/mozilla/ichnaea/issues/2065
MLS was how #GeoClue could get a meters-accurate location without a #GPS receiver / sky line-of-sight.
It was used by many #GNOME / #KDE apps to get instantaneous neighborhood-level location (for maps, local weather…) on #Linux laptops.