Problems with mixed S/MIME - PGP Environements

Expected behavior

Replying via Email Program to Chat Message - visible message in app

Actual behavior

As S/MIME is the preferred encyprtion standard in Emails (companies strongly prefer that), the email reply out of Thunderbird e.g. is automatically S/MIME encrypted for know recipients. In the chat-app on Android, only the encrypted part is shown.


  • Delta Chat Addon for Thunderbird: In case of a chat message, the appropriate PGP key is selected for encryption
  • S/MIME decoind capabilities to be included (and certificate management for S/MIME also)