group chat are like addition function of amethyst app. If you create a group, other must have the URL (seem like discord url) to join.
Discussion
Ah OK.
Well check the spam here. You see wine has basically no spam on relay and filter is 0. For me it was damus relay. I just turned off global and all fine.
Group chats are NOT filtered by filter.nostr.wine intentionally because otherwise you would be missing content.
I haven’t used Amethyst but my understanding is you must uncheck the “person” icon by filter.nostr.wine on Amethyst to stop it from reading in group chats.