Mozilla has just unveiled Thunderbird version 137 of its widely adopted free and open-source desktop email client, now available for download. One of the more notable platform-specific updates comes on the Linux side. The system tray icon has been temporarily disabled until it gains full functionality.
Meanwhile, Windows users get a small but practical upgrade—mail folders are now stored using their file names, a change that could aid in organization and user clarity, especially for those managing large inboxes.
As always, we have a whole host of bug fixes. For example, Thunderbird now properly handles high contrast mode by ensuring in-app notifications display as intended, enhancing accessibility for visually impaired users.
Also worth highlighting is that the frustrating issue where replying from local or unified folders would fail if the message pane was hidden has been resolved.
Performance has also been a focus this time around. Users who found Thunderbird sluggish when opening .eml files or moving large volumes of messages will be pleased to see significant improvements here.
Other key fixes include better behavior in threaded search views, smoother scrolling in RSS feeds, and a number of improvements to OpenPGP key handling and message security.
Regarding reliability, Thunderbird tackled several stability bugs—ranging from crashes caused during shutdown searches to errors when importing mail or dealing with corrupt address book databases. In short, users should notice a more stable experience overall.
Lastly, Thunderbird 137 does deliver some quality-of-life improvements. There are cleaner menu interactions, better spacing in dialogs (like the Feed Account Wizard), and a corrected display of line spacing in the message list.
For more information, see the announcement. Those eager to immediately download the latest Thunderbird version can do so directly from Mozilla’s server.
