[Dovecot] Thunderbird, IDLE, mailbox not always SELECTed

[Tom Alsberg]

Hi there.

Although it does not seem to be a Dovecot issue, I'm sending this here
as people in this list may know better where exactly the problem is.

I am working on Dovecot 1.0 (.alpha5, right now), with the aim that
when Dovecot becomes stable we can put that into production.  Recently
after being more clear with the behaviour (I'm most into namespaces
and mbox/maildir mixing issues, as you can see from my past messages),
I have adopted a few (two, right now, with the third one gone)
"Guinea-Pigs" to use the experimental IMAP server - people who very
much want an IMAP service here and thus may help me test bugs.

One of them reported, that he does not always see new mail.  That user
is using Mozilla Thunderbird (1.0.7).  Looking a bit with him at the
workings, I can see the issue.  He has the IDLE extension enabled.
However when sniffing the network, I see that sometimes when switching
to another mailbox, the SELECT command is not always sent to the
server.  At the beginning, INBOX is (always) selected.  Then another
mailbox is selected, and usually a SELECT command is sent and the
mailbox is seen.  But going back to INBOX again, often no "SELECT
INBOX" is seen on the wire.  Then of course he sees no "EXISTS" or
anything like that.

I wonder if anyone else has observed this, or in some other way, that
Thunderbird does not always show new mail.

Sometimes it appears that a mailbox is selected in Thunderbird, and
Thunderbird immediately (remembering from its cache) does a FETCH to
show the message in the mailbox/folder, but not SELECT to update the
folder itself.

Can caching in Thunderbird be completely disabled, so that every
action will be done against the server?

  Regards,
  -- Tom

-- 
  Tom Alsberg - hacker (being the best description fitting this space)
  Web page:	http://www.cs.huji.ac.il/~alsbergt/
DISCLAIMER:  The above message does not even necessarily represent what
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