Re: [Extra] [EXT] Robert Wilton's No Objection on draft-ietf-extra-imap-fetch-preview-10: (with COMMENT)

[Michael Slusarz <[e-mail]>]

> On 10/05/2020 2:54 AM Robert Wilton via Datatracker <[e-mail]> wrote:
> 
> One minor comment:
> 
>    This standardized display can reduce user confusion when using
>    multiple clients, as abbreviated message representations in clients
>    will show identical message contents.
> 
> I didn't really find this reasoning to be compelling, and perhaps it could be
> removed.  In my experience the amount of preview displayed depends on client
> behaviour or settings (e.g., how much space to allow for previews).

Hypothetical: a message with two alternative parts - text and HTML.  The text part is a "your client doesn't support HTML message" placeholder, the HTML part is the "real" data.  One client may try to create a preview out of the most feature-rich alternative (HTML); another will create a preview out of the first sequential text part it finds.  Another example would be competency in HTML -> plaintext parsing.

I will agree that user confusion is not a major issue if preview display differs based on UI concerns: Are the first 40 characters displayed or the first 100 characters?  However, if the content is vastly different then I do think there is chances for confusion, especially for users that use previews as a way to contextually scan their mailboxes.

"Consistent previews across clients" was a product ask when this feature was first being developed.  Is it the most important feature?  Maybe not.  But it seems important enough to justify a mention since it does clean up, at best, a minor annoyance and, at worst, a real source of confusion that end-users have complained about in the past.

michael