Mozilla has released Thunderbird version 146 of its widely adopted free and open-source desktop email client, now available for download.
On the new features side, the update introduces UI-based configuration of a preferred OpenPGP keyserver, giving users clearer control over where their public keys are fetched and published. Alongside this, Thunderbird migrates all existing logins to modern AES-based cryptography, improving security without requiring user action.
The release also resolves a broad set of issues across core mail workflows. Crashes related to server subscription logic and folder renaming have been fixed, and memory cleanup has been improved when opening new windows from the folder pane.
Additionally, several long-standing folder-handling bugs are addressed, including incorrect naming in the account column, the inability to distinguish similarly named folders in Recent Destinations and Favorites, and improper sorting of the Recent Destinations submenu. Plus, message composition reliability is also improved, fixing cases where no new message could be created when the folder pane was empty.
Attachment and context menu behavior sees important corrections, including preventing the Delete button from removing attachments instead of messages, restoring the Delete option when multiple IMAP folders are selected, and fixing attachment dragging on macOS. vCard handling now works correctly in both the import dialog and when opening VCF files directly from the file manager or command line.
Account Hub, the new Thunderbird’s unified interface used to set up, configure, and manage email accounts, address books, and related services, receives attention, with fixes addressing inaccurate success messages, missing default outgoing configuration, failures when creating EWS accounts, and cases where a local address book could be created with a blank name.
EWS improvements continue with corrected offline folder behavior and restored folder property functionality. Lastly, additional fixes ensure accurate OpenPGP expiration changes, proper signing and encryption when invoking Thunderbird with the compose flag, and correct display of detailed certificate exception dialogs.
For more information, see the announcement. Thunderbird 146 is available as a direct download from thunderbird.net.
