Questions about SPECIAL-USE IMAP extension [1 answer, 1 followup]

[Joseph Tam]

On Thu, 11 Jan 2018, Joseph Tam wrote:

> I'd like to configure my dovecot service to use the IMAP SPECIAL-USE
> extension, but have a few questions for those who have used them, or
> are knowledgable about its use.

Thanks to all who contributed, even if the answer was "it depends".
After configuring it, so far, so good.  One of my users did experience
some confusion, which answered my question ...

> Q2) Will SPECIAL-USE enabled mail clients switch the mailbox used for
> outgoing mail from whatever it was using (e.g. "Sent Mail") to the
> (new) special-use mailbox "xxx"?

The answer to this is an emphatic "yes" for some clients (e.g. Mac OS X
Mail 11.2).  This client will also relabel the actual mailbox "xxx" with
its special-use name "Sent", which can cause confusion when discussing
which mailbox you're referring to.

One thing I didn't take into account was namespace aliasing: I aliased
the former UW imapd namespace (mail/), to conform to the current default
namespace ('').  However, the special-use configuration did not apply
to the aliased namespaces.  Will I have to copy all the special-use
configuration to all my aliased namespaces, or is there some syntax
magic I can use?

By the way, this is the IMAP incantations one can use to test special-use:

 	C: x2 LIST (SPECIAL-USE) "" %
 	S: * LIST (\NoInferiors \UnMarked \Drafts) "/" Drafts
 	S: * LIST (\NoInferiors \UnMarked \Sent) "/" xxx
 	S: x2 OK List completed (0.005 + 0.000 + 0.004 secs).

 	C: x3 LIST (SPECIAL-USE) "mail/" %
 	S: x3 OK List completed (0.011 + 0.000 + 0.010 secs).

Joseph Tam <jtam.home at gmail.com>