imap: strip whitespace from Message-Id and In-Reply-To

Outlook.com is generating fairly long Message-IDs and using folding[0]
to put the ID on a new line. This is resulting in the Message-ID to
contain a leading white space, which is preventing `TrimPrefix` from
removing the less than symbol. When replying the In-Reply-To header will
then contain "< <message-id>" which is not desired and prevents email
clients or lists form correctly associating the email replied to. For
example lore.kernel.org[1]. Trimming tabs, newlines, and spaces from
Message-ID resolves the issue.

[0]: https://datatracker.ietf.org/doc/html/rfc822#section-3.1.1
[1]: https://lore.kernel.org/git/D4U1RWVWEW5D.2T853XSBO1FPA@swagemakers.org/#t

Changelog-fixed: Remove unwanted less than symbol from In-Reply-To
 header when Message-ID uses folding.
Signed-off-by: Julian Swagemakers <julian@swagemakers.org>
Acked-by: Robin Jarry <robin@jarry.cc>

0 files changed, 0 insertions, 0 deletions