This change transmits the original JID of the sender (in decrypt) or receiver(s) (in encrypt).
Handling of MUC is not complete. It is possible that some participants have access to realjids while others don't (e.g., moderators in semi-anon MUCs).
The code currently doesn't handle this and this will cause at least two issues:
- Sending an encrypted message in a semi-anon MUC would reveal the sender's identity (public key)
- Recipients wouldn't be able to decrypt this message as they don't have access to the sender's realjid. Unless they already have the bundle available and then they could associate the public key with a jid (another privacy issue/defeating the point of semi-anon rooms).
This should be fixed, but I'll be merging anyway as it introduces a needed feature. The rest should come soon.