Thunderbird 143 is out with bug fixes, bug fixes and more bug fixes.

The latest monthly update to the venerable open source e-mail client from MZLA Technologies focuses on fixes and fine-tuning the existing set of features, rather than debuting any new ones.

The Thunderbird 140 release brought a sizeable set of improvements, and last month’s Thunderbird 142 added a couple too (like digital signatures in PDFs). It’s no bad thing to see devs take a breath to double-down on refinement.

So what have they been busy fixing over this past month?

Thunderbird 143: Fixes Galore

Anyone irritated by arrow key selection in the global search bar skipping every other result will be relieved to hear that’s resolved.

Similarly, Thunderbird users who hit issues sending mail through smtp-relay.gmail.com can breath a sigh of relief that that snafu is now sorted.

On macOS, the Cmd + Shift + F keyboard shortcut will once again trigger “Search Messages”. On Windows, Windows clicking on a new message notification will bring Thunderbird to the foreground, which was often not happening in earlier builds.

An array of “crashes” have been addressed, including one that could happen during mail import and another that could happen on startup. And in certain situation, adding a new account will no longer fail and cause the app to lock up and freeze.

Among other issues resolved with this update:

  • Web pages with bad certificates displayed as blank
  • Option added to create new address book under File > New
  • Some folders showed new mail count prior to receiving mail
  • Menu Bar > View contained duplicate accelerator keys
  • Drag-drop of unselected contact inserted wrong email address
  • Attachment management did not work on some IMAP servers
  • Saving a new draft retained superceded version
  • Language field in Settings was empty when using Troubleshoot Mode

Rounding things is a fresh set of security patches.

Download Thunderbird 143

Download Thunderbird for Linux, Windows, and macOS from the official website. Downloads will default to monthly release builds (which as of writing, will be Thunderbird 143). Those wanting less feature churn should download the Extended Support Release (ESR).

Upgrading to a new Thunderbird release is easy, though it depends on which platform or packaging format is involved.

For monthly release builds on Windows or macOS, updating takes place inside of Thunderbird: open Thunderbird, go to the Help menu and select About. Thunderbird will check for and apply any available update, and prompt to restart to apply them.

The same method will work on the binary build for Linux (available to download from the Thunderbird website, see above). DEB, Flatpak and Snap builds update through package managers, not inside the app itself.

Anyone using the Thunderbird ESR, which the Thunderbird Snap Ubuntu offers defaults to, will receive feature updates and critical fixes to a separate cadence.