Thunderbird 78.6.1 released with fixes and improvements

Mozilla Thunderbird Icon

Mozilla releases Thunderbird 78.6.1, a security update to the app that also includes a number of improvements and general fixes. It is now available for download for Windows, mac OS and Linux. Mozilla Thunderbird Banner

Thunderbird is my preferred email client of choice. I use this app on every PC and on every operating system I use. It is stable, contains all the features you need, supports add-ons and also comes with a useful RSS reader. I am using Thunderbird for many years and never felt the need to look for an alternative.

Thunderbird 78 doesn't support classic XUL add-ons any longer, but includes some of their features out-of-the-box. For example, on Windows you can minimize the app to the system tray.

The following changes have been made to the app.

What's in Thunderbird 78.6.1


  • MailExtensions: browserAction, composeAction, and messageDisplayAction toolbar buttons now support label and default_label properties


  • Running a quicksearch that returned no results did not offer to re-run as a global searchMessage search toolbar fixes
  • Very long subject lines distorted the message compose and display windows, making them unusable
  • Compose window: Recipient addresses that had not yet been autocompleted were lost when clicking Send button



  • Compose window: New message is no longer marked as "changed" just from tabbing out of the recipient field without editing anything


  • Account autodiscover fixes when using MS Exchange servers


  • LDAP address book stability fix


  • Messages with invalid vcard attachments were not marked as read when viewed in the preview window


  • Chat: Could not add TLS certificate exceptions for XMPP connections


  • Calendar: System timezone was not always properly detected


  • Calendar: Descriptions were sometimes blank when editing a single occurrence of a repeating event


  • Various printing bugfixes


  • Visual consistency and theme improvements


  • Various security fixes

Download Thunderbird

Download Thunderbird

The release notes are available here.

Support us

Winaero greatly relies on your support. You can help the site keep bringing you interesting and useful content and software by using these options:

If you like this article, please share it using the buttons below. It won't take a lot from you, but it will help us grow. Thanks for your support!

Author: Sergey Tkachenko

Sergey Tkachenko is a software developer who started Winaero back in 2011. On this blog, Sergey is writing about everything connected to Microsoft, Windows and popular software. Follow him on Telegram, Twitter, and YouTube.

4 thoughts on “Thunderbird 78.6.1 released with fixes and improvements”

  1. Please, can anyone tell me if thunderbird works with google calender again (like it had for ages until mozilla broke it) after this update?

      1. FYI It is still broken.

        It has been broken since what ever version came after 68.8.1.

        The problem: When you open thunderbird and open the calender tab, any google calenders you have added using the ‘provider for google calender’ add-on are hidden even though they are not marked as hidden..

        If you hide and then unhide them, then they will display correctly.

        If you close thunberbird and reopen it, the calenders are hidden once again so you must repeat the hide/unhide every time you open thunderbird.

        To test the newest version I downloaded the .msi installer from the official website and installed it on a different Windows 10 PC with a local account that had never had thunderbird on it.

Leave a Reply

Your email address will not be published.

Exit mobile version
Using Telegram? Subscribe to the blog channel!
Hello. Add your message here.