Mailbox is one of the fields routined checked in a general search, and if your target contains an '@', it is the ONLY field tried. Input of "joe" would find mailboxes "joe@..." and "joe%...".

Mailboxes are stored in the database with the host part canonicalized, that is, made official. If you use a non-official hostname or nickname, it is automatically canonicalized for you before the search. If the named host is not known, the search is performed anyway on the exact target string.

You may search for mailboxes any of three ways:

Looks for mailboxes with a username part of
"user" on any host. This is a fast search.
Finds ALL mailboxes on host "host". This is a SLOW search.
Looks for an exact mailbox match, user andhost parts both. This is fastest.
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