mh-invisible-header-fields-internal

mh-invisible-header-fields-internal is a variable defined in `mh-e.el'.
Its value is

("Abuse-Reports-To:" "Accept-Language:" "AcceptLanguage:" "Accreditor:" "Also-Control:" "Alternate-recipient:" "Approved-By:" "Approved:" "Article-Names:" "Article-Updates:" "Authentication-Results:" "Auto-forwarded:" "Autoforwarded:" "Bestservhost:" "Bounces-To:" "Bounces_to:" "Bytes:" "Cancel-Key:" "Cancel-Lock:" "Comment:" "Content-" "Control:" "Conversion-With-Loss:" "Conversion:" "Delivered-To:" "Delivery-Date:" "Delivery:" "Discarded-X400-" "Disclose-Recipients:" "Disposition-Notification-Options:" "Disposition-Notification-To:" "Distribution:" "DKIM-" "DL-Expansion-History:" "DomainKey-" "DomainKey-Signature:" "Encoding:" "Envelope-to:" "Errors-To:" "Expires:" "Expiry-Date:" "Face:" "Followup-To:" "For-Approval:" "For-Comment:" "For-Handling:" "Forwarded:" "From " "Generate-Delivery-Report:" "Importance:" "In-Reply-To:" "Incomplete-Copy:" "Keywords:" "Language:" "Lines:" "List-" "Mail-Copies-To:" "Mail-Followup-To:" "Mail-from:" "Mail-Reply-To:" "Mailing-List:" "Message-Content:" "Message-Id:" "Message-Type:" "Mime-Version" "Msgid:" "NNTP-" "Obsoletes:" "Old-Return-Path:" "OpenPGP:" "Original-Encoded-Information-Types:" "Original-Lines:" "Original-Newsgroups:" "Original-NNTP-" "Original-Path:" "Original-Received:" "Original-Recipient:" "Original-To:" "Original-X-" "Origination-Client:" "Originator:" "P1-Content-Type:" "P1-Message-Id:" "P1-Recipient:" "Path:" "Pics-Label:" "Posted-To:" "Precedence:" "Prev-Resent" "Prevent-NonDelivery-Report:" "Priority:" "Read-Receipt-To:" "Received-SPF:" "Received:" "References:" "Registered-Mail-Reply-Requested-By:" "Remailed-" "Replaces:" "Replied:" "Resent-" "Return-Path:" "Return-Receipt-Requested:" "Return-Receipt-To:" "Seal-Send-Time:" "See-Also:" "Sensitivity:" "Speech-Act:" "Status:" "Supersedes:" "Telefax:" "Thread-" "Thread-Index:" "Thread-Topic:" "Translated-By:" "Translation-Of:" "Ua-Content-Id:" "Via:" "X-Abuse-and-DMCA-" "X-Abuse-Info:" "X-Accept-Language:" "X-Ack:" "X-ACL-Warn:" "X-Admin:" "X-Administrivia-To:" "X-AMAZON" "X-AnalysisOut:" "X-AntiAbuse:" "X-Antivirus-Scanner:" "X-AOL-IP:" "X-Apparently-From:" "X-Apparently-To:" "X-Attribution:" "X-AuditID:" "X-Authenticated-Info:" "X-Authenticated-Sender:" "X-Authentication-Info:" "X-Authentication-Warning:" "X-Authority-Analysis:" "X-Auto-Response-Suppress:" "X-Barracuda-" "X-Bayes-Prob:" "X-Beenthere:" "X-BFI:" "X-Bigfish:" "X-Bogosity:" "X-BPS1:" "X-BPS2:" "X-Brightmail-Tracker:" "X-BrightmailFiltered:" "X-Bugzilla-" "X-Cam-" "X-Campaign-Id:" "X-Campaign:" "X-Campaignid:" "X-CanIt-Geo:" "X-Cloudmark-SP-" "X-Comment:" "X-Complaints-To:" "X-Completed:" "X-Confirm-Reading-To:" "X-Content-Filtered-By:" "X-ContentStamp:" "X-Country-Chain:" "X-Cr-Hashedpuzzle:" "X-Cr-Puzzleid:" "X-Cron-Env:" "X-DCC-" "X-Declude-" "X-Dedicated:" "X-Delivered" "X-Destination-ID:" "X-detected-operating-system:" "X-DH-Virus-" "X-DMCA" "X-DocGen-Version:" "X-Domain:" "X-Echelon-Distraction" "X-EFL-Spamscore:" "X-eGroups-" "X-EID:" "X-ELNK-Trace:" "X-EM-" "X-Email-Type-Id:" "X-Enigmail-Version:" "X-Envelope-Date:" "X-Envelope-From:" "X-Envelope-Sender:" "X-Envelope-To:" "X-EviteMessageId:" "X-Evolution:" "X-ExtLoop" "X-Face:" "X-Facebook" "X-FB-SS:" "X-fmx-" "X-Folder:" "X-Forwarded-" "X-From-Line" "X-FuHaFi:" "X-Generated-By:" "X-Gmail-" "X-Gnus-Mail-Source:" "X-Google-" "X-Google-Sender-Auth:" "X-Greylist:" "X-Habeas-" "X-Hashcash:" "X-Headers-End:" "X-HPL-" "X-HR-" "X-HTTP-UserAgent:" "X-Hz" "X-Identity:" "X-IEEE-UCE-" "X-Image-URL:" "X-IMAP:" "X-Info:" "X-IronPort-" "X-ISI-4-30-3-MailScanner:" "X-J2-" "X-Jira-Fingerprint:" "X-Junkmail-" "X-Juno-" "X-Key:" "X-Launchpad-" "X-List-Host:" "X-List-Subscribe:" "X-List-Unsubscribe:" "X-Listprocessor-" "X-Listserver:" "X-Loop:" "X-Lrde-Mailscanner:" "X-Lumos-SenderID:" "X-mail_abuse_inquiries:" "X-Mail-from:" "X-MAIL-INFO:" "X-Mailer_" "X-MailFlowPolicy:" "X-Mailing-List:" "X-MailingID:" "X-Mailman-Approved-At:" "X-Mailman-Version:" "X-MailScanner" "X-Mailutils-Message-Id" "X-Majordomo:" "X-Match:" "X-MaxCode-Template:" "X-MB-Message-" "X-MDaemon-Deliver-To:" "X-MDRemoteIP:" "X-ME-Bayesian:" "X-Message-Id" "X-Message-Type:" "X-MessageWall-Score:" "X-MHE-Checksum:" "X-MIME-Autoconverted:" "X-MIMEOLE:" "X-MIMETrack:" "X-Mms-" "X-Mozilla-Status:" "X-MS-" "X-Msmail-" "X-MSMail-Priority" "X-MXL-Hash:" "X-NAI-Spam-" "X-News:" "X-Newsreader:" "X-No-Archive:" "X-Notes-Item:" "X-Notification-" "X-Notifications:" "X-OperatingSystem:" "X-Oracle-Calendar:" "X-ORBL:" "X-Orcl-Content-Type:" "X-Organization:" "X-Original-Arrival-Type:" "X-Original-Complaints-To:" "X-Original-Date:" "X-Original-To:" "X-Original-Trace:" "X-OriginalArrivalTime:" "X-Originating-Email:" "X-Originating-IP:" "X-pair-" "X-PGP:" "X-PID:" "X-PMG-" "X-PMX-Version:" "X-Policyd-Weight:" "X-Postfilter:" "X-Priority:" "X-Proofpoint-" "X-Provags-ID:" "X-PSTN-" "X-Qotd-" "X-RCPT-TO:" "X-Received-Date:" "X-Received:" "X-Report-Abuse-To:" "X-Request-" "X-Resolved-to:" "X-Return-Path-Hint:" "X-RIM-" "X-RM" "X-RocketYMMF:" "X-Roving-" "X-SA-Exim-" "X-Sasl-enc:" "X-SBClass:" "X-SBNote:" "X-SBPass:" "X-SBRS:" "X-SBRule:" "X-Scanned-By:" "X-Sender-ID:" "X-Sender:" "X-Sendergroup:" "X-Server-Date:" "X-Server-Uuid:" "X-Service-Code:" "X-SFDC-" "X-Sieve:" "X-SMFBL:" "X-SMHeaderMap:" "X-SMTP-" "X-Source" "X-Spam-" "X-Spam:" "X-SpamBouncer:" "X-SPF-" "X-Status" "X-Submission-Address:" "X-Submissions-To:" "X-Sun-Charset:" "X-Telecom-Digest" "X-TM-IMSS-Message-ID:" "X-Trace:" "X-UID" "X-UIDL:" "X-Unity" "X-UNTD-" "X-URI:" "X-URL:" "X-USANET-" "X-Usenet-Provider" "X-UserInfo1:" "X-VGI-OESCD:" "X-VirtualServer:" "X-VirtualServerGroup:" "X-Virus-" "X-Vms-To:" "X-VSMLoop:" "X-WebTV-Signature:" "X-Wss-Id:" "X-X-Sender:" "X-XPT-XSL-Name:" "X-xsi-" "X-XWALL-" "X-Y-GMX-Trusted:" "X-Yahoo" "X-Yahoo-Newman-" "X-YMail-" "X-ZixNet:" "X400-" "Xref:")

Documentation:
List of default header fields that are not to be shown.

Do not alter this variable directly. Instead, add entries from
here that you would like to be displayed in
`mh-invisible-header-fields-default' and add entries to hide in
`mh-invisible-header-fields'.