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Mbox file headers

  • 1 cavab
  • 1 has this problem
  • 14 views
  • Last reply by Matt

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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?
Attached screenshots

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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