[MlMt] JMAP support

[Sam Hathaway]

On 11 Jan 2019, at 14:58, Randall Gellens wrote:

> An IMAP-JMAP proxy just moves the complexity of dealing with the 
> myriad of IMAP servers from core MailMate to an embedded proxy.  I 
> don't see it providing that much help, while it would undoubtedly 
> introduce its own set of problems.

If coordinated right, it would centralize the thankless work of kludging 
around nonstandard, broken IMAP server implementations. Imagine if, 
instead of each MUA author having to develop, test, and maintain dozens 
of ugly hacks, they were collaborating to improve a single JMAP proxy 
codebase that all could use.

> As I said earlier, while JMAP might be very cool, it doesn’t help 
> the core problem of widely variant IMAP server behavior; instead, it 
> just introduces yet more variants.

It does move us towards solving the problem of IMAP being kinda trash 
for resource-constrained clients with slow network connections. I think 
it’s telling that many of the major email providers (Google, 
Microsoft, and FastMail, at least) felt the need to create their own 
proprietary mail access protocols for use by their mobile apps. What 
this says to me is that IMAP is not fit-for-purpose when it comes to 
smartphone apps.