Release Notes

Thunderbird Desktop

Version 115.6.0 | Released December 19, 2023

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.

Happy Holidays from the Thunderbird team. Thank you for a spectacular year!

For more on all the new features in Thunderbird 115, see What’s New in Thunderbird 115.

System Requirements: Details

  • Windows: Windows 7 or later
  • Mac: macOS 10.12 or later
  • Linux: GTK+ 3.14 or higher

What’s Fixed


Message selection misbehaved after selecting a sub-message in an expanded thread, collapsing the thread, then pressing up/down to move selection


Thunderbird now attempts to reconnect on a new connection after SMTP 4xx errors


HTML FileLink attachments used the wrong encoding

Learn What’s Next

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