Finding IMAP mailboxes that have new/unread mail

[Uday Reddy]

Konrad Hinsen writes (viewmail-info, 2011-12-18):

I am trying to use VM for my daily e-mail handling, which mostly involves
an IMAP account with > 100 mailboxes. Messages are sorted into those
mailboxes by the server, so any mailbox is likely to contain new mail at
any time. Is there any way to make VM tell me which mailboxes have new
messages? It would also be nice, though less important, to be able to scan
for mailboxes with unread messages.