[Dovecot] Clients and dovecot-uidlist

Hello,

I'm trying to figure out what exactly (and why) are the consequences of a lost or removal of the dovecot-uidlist file on an IMAP client (Thunderbird for instance).

I took for granted that it was that the client would download all messages again since it might be confused by some UID changes. But I don't really see why (on the IMAP protocol level) and I don't know how to reproduce it.

My understanding is that

. dovecot-uidlist is not recreated until some client selects the mailbox

. the client does something like :

 x UID fetch 1:* (FLAGS)

 to begin with anyway.

So I guess the problem does not occur when no new messages arrive on the mailbox since the same UIDs would be assigned to the same messages ?

But why would that change ? In which situation ?

But can you show me some IMAP protocol command exchange that would illustrate

. when such a problem can occur . how the client would detect that there has been some UID corruption . how it would fix it

Thanks

-- Thomas Hummel