FreeGameDev

That would be for voice and video chat... so only complementary to this topic

for me, irc is good enough. So, well "other" as in "just irc". Otherwise, any sofware that can be built is ok (means, not python,no perl, no php, no web). But I'll adapt for my hosts

I think for now we have solved this topic

There is a modern IRC webclient here: https://freegamedev.net/irc/ and the channels are also accessible through a XMPP gateway.