Adding a friend instance generated a UI link to an xml file

We can see this on https://demo.gancio.org/, we going to 'Friends>Sa Pratza' we are sent to an xml file instead of the web ui, ie. we get https://sapratza.in//federation/u/Sa%20Pratza instead of https://sapratza.in/ Same thing when adding mobilizon accounts, eg. adding https://mobilizon.fr/@jeuxsurnantes result in a link to https://mobilizon.fr/relay