Nocta Senestra utilise witches.town. Vous pouvez læ suivre et interagir si vous possédez un compte quelque part dans le "fediverse".
is there masto equivalent to discord i.e entirely aping the interface of popular alternative but making is open source / decentralised?
and i ask this as someone who has never and will never use the voice chat in discord
Matrix/Riot
You can test it on riot.im/app for example (keep in mind if you register on matrix.org some functionalities as the online status are disabled).
Or rocket.chat, but I've never tested it.