This crash (at least the one for which the crash report was pasted) was not caused by sending a message but by parsing (most likely for display) a jabber data form with a JID. Which action did you use?
Andrzej Wójcik (Tigase) commented 4 years ago
The issue was caused by filling a jid-multi field with "empty line" instead of a "jid". How should the app react? Ignore this input? or mark field with an error?
wojciech.kapcia@tigase.net commented 4 years ago
I used "Edit configuration"
As for how it should be handled: marking the field with error should be enough I think.
Andrzej Wójcik (Tigase) commented 4 years ago
I've added protection against unexpected string in the input for a JID/BareJID. That will fix this issue, however I'm still considering more extensive change to TigaseSwift to properly validate JID/BareJID during conversion from string.