Thunderbird 91 is Finally Here with A Lot of Improvements

After more than a year of development since Thunderbird 78, Thunderbird 91 arrives full of changes, news and improvements of all kinds.

Thunderbird is a completely free and open source program originally designed by Mozilla (the company responsible for Firefox) as a complete organization suite. This program consists of an email client, a calendar, a to-do list and a chat tool to talk with other colleagues.

The current version of Thunderbird is 78, which was released in July last year. However, those responsible are going to jump directly to version 91 to match the version of Firefox and try to speed up the development of the program a bit.

What’s New in Thunderbird 91

The new version comes with a range of new features and improvements, along with all the improvements Mozilla has prepared in recent months.

Thunderbird 91 is coming with a new account setup wizard, which is much more intuitive now. The new accounts configuration wizard has also been largely redesigned, to be simpler to use and display all the settings the user needs faster.

Thunderbird’s new account setup wizard can now detect and set up CalDAV calendars automatically. It lets you to configure an encryption, by clicking on the “End-to-end encryption” on the page for that. In addition, you’ll be also able to connect to an address book during the setup.

In terms of features, one of the biggest highlights of Thunderbird 91 is the new profile export and import system, which will allow users to quickly backup or restore profiles from other systems.

Integration with Gmail has also improved which is now faster and simpler, besides also making a lot of tweaks in terms of its stability. The new interface should make it easier to read emails and organize them into different accounts, categories or folders.

The Thunderbird 91 user interface includes enhancing the message reading UI, the message compose window has also been revamped, calendar UI improvements, and more.

Other Improvements

  • Thunderbird 91 now operates in multi-process (e10s) mode by default.
  • New user interface for adding attachments.
  • PDF.js viewer now included in Thunderbird.
  • Enable redirect of messages.
  • Allow showing empty CC/BCC rows in compose window.
  • Add support for non-ASCII characters in recipient addresses.
  • Quick Find is now available in the multi-message (thread summary) view.
  • Allow pinning folder views to the Folder Pane.
  • CardDAV address book support.
  • CardDAV address books automatically detected based on provided user information.

Of course, a large number of errors, bugs and problems have also been corrected so that the use of this software is as simple and comfortable as possible.

For detailed information about all changes, you can refer to the Thunderbird 91 release notes.

Download Thunderbird 91

At the moment, Thunderbird 91 is only offered as direct download from the Mozilla FTP and not as an upgrade from Thunderbird version 78 or earlier. It’s available for Windows, Linux, and macOS. A future release will provide updates from earlier versions.

Bobby Borisov

Bobby Borisov

Bobby, an editor-in-chief at Linuxiac, is a Linux professional with over 20 years of experience. With a strong focus on Linux and open-source software, he has worked as a Senior Linux System Administrator, Software Developer, and DevOps Engineer for small and large multinational companies.

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  1. I’m not really seeing any difference except for some very minor UI changes here and there. Oddly it wont allow you to upgrade from 78. You have to do a complete install and there seemed to be now way, that i saw, to import my accounts and settings from 78. I use TB daily as my client but while this was represented as some huge leap, I’m not seeing it at all. It’s like saying the ‘65 Mustang was a big upgrade from the ‘64 1/2. There’s no there, there, to any of the hype.

    • Also, I have 4 webdav calendars and despite them making claims about how easy they are now to setup, I saw no difference between 78 and 91.

      • Here’s another update. CalDav worked for about 24 hours and now won’t work at all. It just keeps prompting me for the password and no matter how many times I put it in and ask it to save the password, it prompts me again seconds later. I have tried to delete the CalDav calendars on TB 91 and then bring them back again with all the proper login info but the same problem occurs, non-stop asking for the password. This is a beta product and is not ready for prime time. Keep 78. It looks almost the same and 78 works.

  2. Unfortunately, TBIRD 91 is not compatible with the excellent ImportExportTools NG which would backup your email on exit.
    Not having a lot of luck finding a replacement yet…. suggestions welcome.

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