Re: [Jmap] the large email (attachment) problem

Bron Gondwana <> Mon, 02 August 2021 02:42 UTC

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Date: Mon, 02 Aug 2021 12:42:26 +1000
From: "Bron Gondwana" <>
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Subject: Re: [Jmap] the large email (attachment) problem
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On Mon, Aug 2, 2021, at 11:37, Neil Jenkins wrote:
> On Mon, 2 Aug 2021, at 03:43, John R Levine wrote:
>> I agree there is a bootstrap problem.  Some mail programs implemented it 
>> back in the 1990s when people still dialed in to download their mail, then 
>> it went away when we all got permanently online, now we need it again as 
>> the size of bloatware has pulled away from what mail systems do.
> I *think* the bootstrap problem can be solved if most clients support multiple MIME parts correctly (which I think they probably must, because Apple's clients often produce bodies like that). You have something like this:
> multipart/mixed
>     text/html *(The message body)*
>     multipart/alternative
>         text/html *(HTML representation of attachments, just like current G Drive etc.)*
>         message/external-body *(For external attachment aware clients)*

We've collected a bunch of great ideas here.  I think the next sensible step is probably some running code and maybe try to get a group of hackathon people trying things at the next IETF.

I'm particularly interested in anyone who knows any clients which currently implement `message/external-body` at all, so we can check that they handle any changes we make to the format.

  Bron Gondwana, CEO, Fastmail Pty Ltd