Thunderbird 78.3.0 and 78.3.1 have been released

Martin Brinkmann
Sep 26, 2020
Updated • Sep 26, 2020
Email, Thunderbird

MZLA Technologies Corporation has released two new versions of the Thunderbird desktop email client this week.  Thunderbird 78.30 was released on September 24, 2020, and Thunderbird 78.3.1 just two days later on September 26, 2020.

Thunderbird installations that have not received either update yet are updated to version 78.3.1 automatically. Users of the email client can select Help > About Thunderbird to check the installed version and run a manual check for updates. The new release is also available as a manual download from the project's website.

Why two versions? A second version is pushed when the previous version has at least one critical issue, be it security or non-security, that has the potential to affect a large number of users. In this case, Thunderbird 78.3.1 fixes a crash that users experienced after Thunderbird was updated to version 78.3.0.

All changes of Thunderbird 78.3.0 are part of the minor update as well. It is a minor release that fixes non-security and security issues for the most part, and includes some improvements next to that.

The official release notes highlight OpenPGP improvements in this release. The decryption performance of large messages has been improvement when OpenPGP is used, and the external key UI is not shown when disabled in the preferences.

Other changes include that the installation of legacy extension has been disabled in that release, that the account setup wizard displays a popup when a server uses a self-signed SSL/TLS certificate, and that the reply-to header now appears under the From header. Lastly, this release includes unspecified improvements to the calendar's sidebar user interface.

As far as fixes are concerned, there are plenty:

  • Selecting "Cancel" on the Master Password prompt at startup incorrectly reported corrupted OpenPGP data
  • OpenPGP: Creating a new key pair did not automatically select it for use
  • Dragging & Dropping recipient pills resulted in lost pills when an error was present
  • Spellcheck suggestions were unreadable in dark theme
  • Calendar: Multiple password prompts opened
  • Linux Distributions: UI was not rendered completely when built without updater
  • MailExtensions: browser.folders.delete failed on IMAP folders

Thunderbird 78.3 resolves several security issues, one of which is rated high, the second highest rating after critical. A total of four security issues are fixed in the release, the remaining three have received a rating of moderate each.

The developers list a single known issue: the mailing list is not focused on startup.

Now You: do you use Thunderbird? What is your take on the 78.x version of the email client?

Thunderbird 78.3.0 and 78.3.1 have been released
Article Name
Thunderbird 78.3.0 and 78.3.1 have been released
MZLA Technologies Corporation has released two new versions of the Thunderbird desktop email client this week.  Thunderbird 78.30 was released on September 24, 2020, and Thunderbird 78.3.1 just two days later on September 26, 2020.
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  1. JMGG said on January 19, 2012 at 8:25 am

    You said that Outlook isn’t your main email client, so which is your main one?

    1. BalaC said on January 19, 2012 at 9:42 am

      I think its thunderbird

    2. Martin Brinkmann said on January 19, 2012 at 10:15 am

      It is Mozilla Thunderbird.

  2. Salaam said on September 24, 2012 at 9:52 pm

    Awesome! This actually solved my problem… what a stupid bug.

  3. Claud said on December 19, 2012 at 2:08 am

    If this is the same bug that I’ve encountered, there may be another fix: (1) hover over open Outlook item in Taskbar, cursor up to hover over Outlook window item, and right-click; (2) this should give you Restore / Move / Size / Minimize / Maximize — choose Move or Size; (3) use your cursor keys, going arbitrarily N/S/E/W, to try to move or size the Outlook window back into view. Basically, the app behaves as though it were open in a 0x0 window, or at a location that’s offscreen, and this will frequently work to resize and/or move the window. Don’t forget to close while resized/moved, so that Outlook remembers the size/position for next time.

    1. Lynda said on February 12, 2013 at 3:37 pm

      THANK YOU Claude!!! I could get the main window to launch but could not get any other message window to show on the desktop. You are my hero!!!!

    2. Chad said on November 20, 2018 at 4:24 pm

      Solved my issue! 6 years later and this is still problem…

    3. Ivan X said on January 21, 2021 at 4:50 pm

      Fantastic. Thank you. Size did the trick.

  4. Andrew said on October 26, 2013 at 7:06 am

    This solved my Outlook problem, too. Thank you. :)

  5. Charles said on December 7, 2013 at 7:23 pm

    Thank you so much, this started happening to me today and was causing big problems. You are a life saver, I hope I can help you in some way some day.

  6. garth said on November 7, 2014 at 7:13 pm

    You are a god – thank you!

  7. Faisal said on February 9, 2015 at 10:09 am

    thanks a lot…. work like charm.. :-)

  8. Simon said on March 24, 2015 at 11:36 pm

    Yah…thanks Claude. I’ve been having the same problem and tried all the suggestions…your solution was the answer. It had resized itself to a 0/0 box. Cheers

  9. Olu said on April 14, 2015 at 1:35 pm

    Excellent post. This had me baffled even trying to accurately describe the problem. This fixed it for me.
    Thank you

  10. Coenig said on July 23, 2015 at 7:36 am

    Thanks a lot for the article. Don’t know why it happenend, don’t know how it got fixed, but it was really annoying and now it works :-)

  11. Fali said on January 20, 2016 at 4:19 pm

    Thanks a lot. I was facing this issue from past 3 week. I tried everything but no resolution. The issue was happening intermittently and mainly when I was changing the display of screen ( as i use 2 monitors). The only option i had was to do system restore. But thanks to you.

    1. MIki said on January 10, 2019 at 11:54 am

      I’ve been tried to sole this problem for 12hours. Your comment about changing the display of screen helped me a lot!! Thanks!!

  12. Christina said on January 20, 2016 at 6:14 pm

    Thank you…don’t know why this happened but your instructions helped me fix it. Running Windows 10 and office pro 2007

  13. Oz said on July 22, 2016 at 3:20 pm

    Great tip! Thanks!

  14. Tracy said on September 1, 2016 at 4:48 pm

    Worked for me, too – thank you!!!

  15. shawn said on September 9, 2016 at 10:25 am

    It’s Worked for me, too
    thank you very much!

  16. Jari said on October 31, 2016 at 11:53 am

    I had a similar issue with Outlook 2013 on Windows 10 and this helped me to fix it. Thank you very much!

  17. Michel H said on November 30, 2016 at 11:08 pm

    Thank you so much. Solved!
    Considering you published this in 2012, incredible not been debugged by Microsoft.
    Thank you again. M

  18. Ziad Bitar said on January 9, 2017 at 2:00 am

    This problem was faced by only one user logging to TS 2008 r2 using outlook 2010.The issue was resolved.


  19. Anonymous said on February 15, 2017 at 5:24 pm

    Great tip. Thank you!!!! If it helps, I had to use the Control Key and the arrow keys at the same time to bring my window back into view. Worked like a charm.

  20. Rochelle said on March 6, 2017 at 11:59 am

    Thank you, this worked !!!!

  21. anom1234 said on May 20, 2018 at 11:20 pm

    Man, you are a fucking god. Thanks a lot, what an annoying bug!!

  22. JC said on October 12, 2020 at 2:14 pm

    Awesome, this post solved the issue. Many thanks!

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