OMEMO group chat messages get lost in ChatSecure, not in Conversations

[wunderf1tz]

Dear devs,

server: ejabberd 20.07-1~bpo10+1, see https://compliance.conversations.im/server/wunderfitzig.net/ client: OMEMO group chat, 5 users, 3 iOS/ChatSecure, 2 Conversations/Android issue: ChatSecure clients don't receive all messages/"some" messages get lost. debugging so far: had all 3 iPhones in front of me and deleted, freshly added all of the contacts to each, "...are friends now" messages appeared, OMEMO key was transferred and accepted. Send/receive private + group OMEMO messages with success afterwards. One week later, messages of iOS clients get lost. Clients on Conversation receive all messages.

Thanks a lot for further problem solving to get this beautiful piece of decentralistic, federalistic software further spread out on this planet. Dev, we need you!