Geospoof will create a new panel in you Development tools that will allow you to control the location provided by Geolocation API. You can set the location by map, coordinates or reproduce a GPX track. You will need to provide a OSM tiles URL to be able to use the extension, e.g: https://{a-c}.yourser.ver/x/y/x/?key This is a development extension it is not meant to be a privacy extension to not reveal your real geolocation. The spoofed position it only will work as long as the developer tools are opened and activated from the Geospoof panel.