[Mimedefang] filter on header from display name

[Marcus Schopen]

Hi,

I see a spammer, who sends with different envelope from and header
from, but the "display name" in header from always contains the same
substring, e.g.:

From: "Spammer <info at spammer.com>" <changing at sender.tld>

The part 
  
  From: "Spammer <info at spammer.com>"

is always the same, but I can't catch it with blacklist_from. Can I get
that from $entity->head->get('From') or any better ideas?

Ciao
Marcus