Oh, great, there’s an RFC, that’s awesome.

Maybe Gmail will just switch to that and no milters will be necessary?

App idea.

Postfix milters that translate Gmail’s dumb reaction format to Delta Chat’s good one, and the other way around. Would only work on the unencrypted threads with Gmail users so the benefit is pretty minor.

I’ve found specs for how the reaction looks on Gmail’s end:

If you have a Debian computer connected permanently to the internet, this document will allow you to be able to:

• receive and store emails for your users
• let your users retrieve the email through IMAP and POP3 - even with SSL to encrypt to connection
• receive and forward (relay) email for your users if they are authenticated
• offer a webmail interface to read emails in a web browser
• detect most spam emails and filter them out or tag them