Neomutt (and probably Mutt too, but I didn't try) seems to be hiding header fields from email, such as the Message-ID field, and fields that are added by SMTP servers when they receive the message.
How can one ask it to show the entire mail source, as if one was reading the file itself?
In other software, such as (Mozilla) Thunderbird, one can ask it to "View Source", which shows everything.
