Comment 141 for bug 119899

This behavior is still present in the most current versions (note message date) of Thunderbird on Ubuntu and SeaMonkey on Windows 7. It does appear to be an issue when applying after the fact to IMAP and POP mail. Someone commented about a search function for AOL. Every webmail account I have, including AOL, has a search function. Many of these *custom* headers are standard headers. The best workaround, in my opinion, is to simply add common headers to future builds. This can also be an issue because occasionally the mail filters cannot find the folder the message is to be moved (another bug?). In my mind, X should imply custom headers since that is the recommended standard. All other common headers should be considered standard.

A suggest list, including those already listed, should contain Authentication-Results, BCC, CC, Content-Type, Content-Transfer-Encoding, Date, Delivered-To, DKIM-Signature, DomainKey-Signature, From, List-Id, List-Subscribe, List-Unsubscribe, Mailing-List, Message-ID, MIME-Version, Precedence, Received, References, Reply-To, Return-Path, Sender, Subject, To.

I'm sure this is not a comprehensive list. Also, some of these may be meaningless and some starting with X might be added. However, the person working on this bug will make the final decision when editing the code. Please offer further suggestions so that we may come to an agreement. I don't think this work around will add bulk or slow down mail.