JMAP Support (or similar) for Thunderbird

[hutcheon]

IMAP is awesome, but has some rough edges around things like IDLE being only able to monitor one folder per connection.  This means users may get an inconsistent experience depending on the number of folders they have, with emails arriving in some showing up immediately, while others have to wait until the regular "check for new messages" check. 

JMAP (for example) removes these problems, and for mobile applications, provide a better experience.

https://jmap.io/spec.html

https://en.wikipedia.org/wiki/JSON_Meta_Application_Protocol

[Alexolog]

Please implement it!

[onequest]

Let's do this! Especially for K9 Mail/Thunderbird Android. 🤞

[eqdynamics]

I endorse this proposal. As a donator I strongly believe Mozilla should be pushing forward new, valuable open source protocols - such as JMAP.

Regarding the 'chicken and egg' debate - well, somebody has to start somewhere. If Mozilla's promises that convinced me to donate are to be believed then here is a chance to put words into action.

JMAP is already appearing in new open-source email servers (eg; Stalwart) and is scheduled to appear soon in long-existing servers such as Dovecot (probably the most widely used), Cyrus, Apache James and others. And clients including Claws Mail, Evolution, Geary, K-9 Mail, Nextcloud ... have outstanding requests. There seems adequate support from already existant libraries (see: https://jmap.io/software.html) to make the process of integrating the protocol a relatively simple one.

If a bounty program is started I'll tip in toward dev and test costs.