@macberg
@smxi
We use BigBlueButton for daily video meetings. I think there's an integration that lets you start a videocall on some external service by clicking on a button in Zulip, but I never used that.
About the security/encryption: I actually don't know, never looked into it 🤷♀️
But I don't think Discord is encrypted...? So for an alternative to Discord, that shouldn't be required anyway.