[Users] Adding a header to incoming/outgoing mail

[Milan Obuch]

On Fri, 22 Jan 2021 11:43:29 +0300, Ivan Krylov <krylov.r00t at gmail.com>
wrote:

> Dear all,
> 
> I was asked to always Cc: "person B" when messaging person A. Person A
> always uses "Reply to sender", so their replies to me never contain
> Cc: "person B" or anything like that, even if I manually add Cc:
> "person B" in my own messages. Can Claws-Mail help me add Cc: "person
> B" automatically? I can write a plugin if I have to.
> 
> Alternatively, is there a way to add a Reply-To: header to incoming
> messages matching certain criteria when using IMAP? It seems to me
> that filters aren't allowed to change the contents of the messages.
> 

If you are able to use server side filtering with message alteration,
this is (relatively) easy.

If you have no control over mail delivery process, you need to do it in
mail client.

Claws Mail client has (officially) two scripting plugin - perl and
python. Perl plugin is older, I have no experience with it, but Python
plugin allows you to script such message alterations.

I wrote Lua plugin, basically doing the same as Python plugin, and it
allows me to change message recipient(s) or add new one based on
arbitrary criteria.

My recommendation would be use Python plugin if you are able to do so.
I would use my plugin because I was not able to use python plugin and
so I created Lua plugin for my own use.

I sent a mail to mailing list some time ago why I was not able to
usePython plugin. If others are interested, I can share my work.

Regards,
Milan