Display Number of Unread Messages and Size of Mail Folders in Mozilla Thunderbird

To view the size of your email folders in Mozilla Thunderbird 3 and the number of unread emails in each folder you need to install this Thunderbird addon: “Extra Folder Columns” because this capability has been removed as a standard Thunderbird feature.


In the folders pane in Mozilla Thunderbird 2, you can display the number of unread messages, the total number of messages, or the size of the mail folder. To do so:

  1. First go to “Tools -> Options -> Advanced -> General Settings”, and check the box for “Show expanded columns in the folder pane.” Click “OK”. This will cause a small drop-down marker to appear in the top-right corner of the folders pane.
  2. By clicking on this drop-down marker, you can then select Unread, Total, and/or Size to be displayed.

16 thoughts on “Display Number of Unread Messages and Size of Mail Folders in Mozilla Thunderbird”

  1. I second ddanila — I’d been looking for a way to show the number of messages in a folder myself, but it’s not exactly obvious what to do …

  2. I used this ‘number of messages’ display in Messenger and was disappointed not to find it in Thunderbird … Until this tip. Thanks!

  3. I recently switched from Evolution to Thunderbird and want to see the # of messages in a folder.
    However, your suggestion doesn’t work in my version of Thunderbird (version 2.0.0.14 (20080505) as the “options” choice is not available in the Tools menu.
    Any suggestion?
    Joep

  4. Thank you for this tip, the fix is sure not obvious! BTW, I am using version 2.0.0.16, and there is certainly an “options” link under “tools,” so perhaps joep should update if there is a problem with the earlier version.

  5. In earlier versions of thunderbird, ‘tools’ -> ‘options’ can be found under ‘edit’ -> ‘preferences’.

  6. So if you want to check ‘Show expanded columns in the folder pane’, this is under ‘edit’ -> ‘preferences’ -> ‘general’ in the older versions.

  7. Joep, in TB 2 you can invoke the advanced config editor, under Tools/about:config.
    Then select property mail.showFolderPaneColumns to true. Then a folder options box appears
    to the right in each main mail folder where you can select to display message unread, total and size.

  8. Just one correction, you can access the advanced config editor via Tools menu *only* if you have the AboutConfig add-on installed. Otherwise it’s under Edit/Preferences/Advanced/Genetal tab/Config editor button.

  9. When I delete messaged the folder size wasn’t updated. So now I have a folder with 0 files yet 7mb of space.

  10. They didn’t remove it permanently. The very top of this page tells you the name of the add-on that will provide this function, ‘Extra Folder Columns’.

    It works.

Leave a Reply

Your email address will not be published. Required fields are marked *