As far as I know Matrix is the best FOSS alternative to Discord right now. Maybe try using the coturn addon for voice instead of Jitsi. I've been able to share audio snippets just fine this way.
I need to find a decent guide to Matrix, I was playing with it a couple of days ago and definitely found it confusing.
I saw Revolt posted in HN recently as a discord alternative. Might be worth a look: https://revolt.chat/
Haven’t tried it myself so unsure about the feature set.
If you're watching movies with friends and want a FOSS alternative, Jellyfin is the way to go. It's basically a way to host a media streaming center that others can connect to. It might be a bit overkill depending on your needs, but it's great for that exact purpose. It doesn't have chat or anything, though, so you'll want to keep something else around for that.
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