Improve matching for message/rfc822
MIME message sometimes also start with either a "Content-Type:" header or a "To:" header.
Content-Type often appears often in encrypted attachments and To: seems to appear sometimes in email from Thunderbird.
MIME message sometimes also start with either a "Content-Type:" header or a "To:" header.
Content-Type often appears often in encrypted attachments and To: seems to appear sometimes in email from Thunderbird.