a counterpart to spam-address.tab would be nice,
ie. a whitelist, with precedence over spam-address.tab.
Then one could do such things like that:
Ie. reject all mails from baddomain.com except from ab...@baddomain.com
(ie. in this case let replies from their abuse address pass thru;
ie. the replies to our complaint mails (abuse reports) sent to them because of
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