Social network Friendica (venera.social instanc), Hubzilla (freehub.space instanc), Misskey (misskey.social instanc). And also, I have many accounts on various servers in Mastodon, PixellFeed and PeerTube. Moreover, some of these servers are no longer available at the moment. I have been interested in this topic for many years and have researched different servers. By the way, I also had accounts in the Diaspora social network on several servers.
I don’t have and have never had anything confidential in Discord and IRC. I use this to chat with strangers in thematic chats.