Rmail reformats the header of each message before displaying it for the first time. Reformatting hides uninteresting header fields to reduce clutter. You can use the t command to show the entire header or to repeat the header reformatting operation.
Reformatting the header involves deleting most header fields, on the
grounds that they are not interesting. The variable
rmail-ignored-headers holds a regular expression that specifies
which header fields to hide in this way--if it matches the beginning of
a header field, that whole field is hidden.
Rmail saves the complete original header before reformatting; to see
it, use the t command (
discards the reformatted headers of the current message and displays it
with the original header. Repeating t reformats the message
again. Selecting the message again also reformats.
One consequence of this is that if you edit the reformatted header (using e; see section Editing Within a Message), subsequent use of t will discard your edits. On the other hand, if you use e after t, to edit the original (unreformatted) header, those changes are permanent.
When used with a window system that supports multiple fonts, Rmail
highlights certain header fields that are especially interesting--by
default, the `From' and `Subject' fields. The variable
rmail-highlighted-headers holds a regular expression that
specifies the header fields to highlight; if it matches the beginning of
a header field, that whole field is highlighted.
If you specify unusual colors for your text foreground and background,
the colors used for highlighting may not go well with them. If so,
specify different colors for the
highlight face. That is worth
doing because the
highlight face is used for other kinds of
highlighting as well. See section Using Multiple Typefaces, for how to do this.
To turn off highlighting entirely in Rmail, set