I don't recall DeltaChat having any issues with metadata leakage, but Matrix for sure has massive issues with that (one of the main reasons I don't use Matrix for sensitive or personal chats). The only current issue is that it doesn't yet support forward secrecy, which the devs said it will be added when they upgrade to autocrypt v2:
https://autocrypt2.org/
https://support.delta.chat/t/off-the-record-chats/1181/8
Mehrad :kde: :emacs: :rstats:
npub1e8…d7zjt
2026-07-03 16:59:57 UTC
in reply to nevent1q…2q0t
Author Public Key
npub1e8hd6qrda9yv3s39u4eka59x43pc0v3ej0ug4c52fz3ka4c6wn8scd7zjtSeen on
wss://relay.momostr.pinkPublished at
2026-07-03 16:59:57 UTCEvent JSON
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