This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Èròjà atẹ̀lélànà yii ni a ti fi pamọ́ fọ́jọ́ pípẹ́. Jọ̀wọ́ béèrè ìbéèrè titun bí o bá nílò ìrànwọ́.

Mbox file headers

  • 1 èsì
  • 1 ní ìṣòro yìí
  • 14 views
  • Èsì tí ó kẹ́hìn lọ́wọ́ Matt

more options

Another test on Gmail email manipulation.

When exporting an email via Google Takeout, the product applies 3 headers specific to the email, including X-GM-THRID and X-Gmail-Labels and a line separator.

What I noticed is that importing the original email without edits, the Mbox file headers do not appear, however if the original email is edited, the Mbox file headers appear.

Is there a reason why it shows when the original email is edited but not if it is in its original form?

Why can't the 3 headers be deleted when editing and subsequently trying to import back to Gmail via Thunderbird?

Another test on Gmail email manipulation. When exporting an email via Google Takeout, the product applies 3 headers specific to the email, including X-GM-THRID and X-Gmail-Labels and a line separator. What I noticed is that importing the original email without edits, the Mbox file headers do not appear, however if the original email is edited, the Mbox file headers appear. Is there a reason why it shows when the original email is edited but not if it is in its original form? Why can't the 3 headers be deleted when editing and subsequently trying to import back to Gmail via Thunderbird?
Ìsopọ̀ yíyà aṣàfihàn

All Replies (1)

more options

Do not appear where?

The only place I would expect to see them would be in the message source (Ctrl+U) and I would expect them to appear there regardless of editing. However a X- headers they are not standards headers and have no intrinsic value in email although some are registered with IANA https://www.iana.org/assignments/message-headers/message-headers.xhtml

Thunderbird's implemented use of those specific headers is covered in this bug from 9 years ago. https://bugzilla.mozilla.org/show_bug.cgi?id=721316