Why does mutt send the content-disposition:inline at the top?

Question

My header from mutt and msmtp setup looks like the following

From [e-mail] Fri Dec 10 12:10:20 2010
Date: Fri, 10 Dec 2010 12:10:20 -0500
From: Name Name <[e-mail]>
To: {0xFACEB00C>>2 in decimal}@fb.com
Subject: hoppity
Message-ID: <[e-mail]>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="LZvS9be/3tNcYl/X"
Content-Disposition: inline
User-Agent: Mutt/1.5.20 (2009-06-14)
Status: RO
Content-Length: 898
Lines: 58

I know how to change the content-disposition for attachments (using ^D) but the one above I cannot seem to remove or change. Why is it there ? and how can I remove it ?

Answer 1

Mutt (as of 1.5.20) always writes a Content-Disposition header when it writes a MIME header. For the toplevel part of a multipart message or a non-multipart message, I think the Content-Disposition is always inline.

While not having full control over a header is annoying (to a mutt user), I wonder why you'd want to change it. If you have a multipart message and don't want to show any part inline, setting each part to attachment should be enough (provided the recipient's MUA handles Content-Disposition as written, which is not always the case). If you have a single-part message but don't want the body to be shown by default, this doesn't correspond to common email habits — I wouldn't expect many MUAs to handle this case.