This is not really a feature proposal, more some thinking around the topic of co-existence of document-style mails and chat-style mails. Document-style mails are those with a subject, on which replies are threaded. Chat-style mails are those that are contact or group-contact based. Chat groups have a title but messages within are not threaded. Chat messages are shown linearly, at time of arrival. Topics tend to mix and rather be “people” based than “subject” based.
Some of us use two e-mail addresses, one with a Document-style and one with a Chat-style e-mail account. Others use the same account for both. The latter is known to cause several troubles, for example double-notifications if you have a document-style e-mail reader on your mobile, along with your Chat one. Or even worse, with Delta Chat’s current BCC-self logic, outgoing messages are notified in the document-style app if Delta was not fast enough to move the message away. We are not using an upload to the IMAP Sent folder because this doubles outgoing network traffic. In this githut core issue there is some discussion around the BCC-self logic which could be optionally turned off … but this is not what i want to talk about here.
This is rather about: what could we do to make using two separate addresses easier, nicer? ideas:
configure Delta Chat to know about the “document-style” address
if the document-style address forwards a mail to the Chat one, DC could show it as coming directly from the original sender, with some indicator. If you DC-reply to it, the In-Reply-To header be set properly so that the other side can know it’s from you. If the original message was a DC message we can make it rather seemless to have a DC-to-DC chat.
DC could allow to easily “bounce” a message to the configured document-style address (leaving the original message as intact as it can). The document-style app would get the bounced e-mail, and could reply to it.
If the doc-style and chat-style app use Autocrypt, they could share the cryptographic setup, so that e2e-encryption could be maintained.
if using the “+” extension, the two addresses could even be on the same IMAP account, say "email@example.com" and "firstname.lastname@example.org", see also Lorenz’ blog post on + extensions with delta chat for how to configure something like this.
There are endless questions around this topic – but i think it’s an interesting one. I am a heavy user of both chat and doc-style e-mail, and think that even some small things could make the experience nicer.