As the Firefox domain name you mentioned above, the purpose is to trigger Captive Portal login pages: https://en.wikipedia.org/wiki/Captive_portal https://en.w

As the Firefox domain name you mentioned above, the purpose is to trigger Captive Portal login pages: https://en.wikipedia.org/wiki/Captive_portal https://en.wikipedia.org/wiki/Captive_portal Basically all browsers / OSes do the same thing to work with it.