Release Notes

Thunderbird Desktop

Version 78.12.0 | Released July 13, 2021

Check out the notes below for this version of Thunderbird. As always, you’re encouraged to tell us what you think, or file a bug in Bugzilla.

For more on all of the new features in Thunderbird 78, see New in Thunderbird 78.0.

System Requirements: Details

  • Windows: Windows 7 or later
  • Mac: macOS 10.9 or later
  • Linux: GTK+ 3.14 or higher

What’s Fixed


Sending an email containing HTML links with spaces in the URL sometimes resulted in broken links


Folder Pane display theme fixes for macOS


Chat account settings did not always save as expected


RSS feed subscriptions sometimes lost


Calendar: A parsing error for alarm triggers of type "DURATION" caused sync problems for some users


Various security fixes

Learn What’s Next

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