@Tutanota @ilpianista @kot Can you explain why you think local storage can't be encrypted? I've encrypted my local storage both at the hardware layer and in software (LUKS). The pgp encrypted email I receive stands as a 3rd layer of encryption.

As for knowing if the msg was sent securely, you seem to be assuming the bridge would entail decrypting the message. If the bridge passes the message as-is, then recipients will obviously know if it was sent using encryption.