Previously the headers-config was only applied to gmail-mailboxes (I guess that was a mistake of my past). This change configures them for all mailboxes. Furthermore I dropped the x-mailer, since I'm really _not_ interested in the sending mail-client... Finally I adjusted the order of the headers, from the, sometimes, awkward default-ordering to my own preferences. Reference: http://www.fefe.de/muttfaq/muttrc