The Thunderbird mail client developers today formally announced Thunderbird 140 as the newest Extended Support Release (ESR) for this cross-platform alternative to Microsoft Outlook.

Thunderbird 140 is a big upgrade over the prior Thunderbird 128 ESR release. Thunderbird 140 now automatically adapts to using the dark message mode as part of the dark mode experience, new appearance settings, native OS notifications across Windows / Linux / macOS, easier account adding with the Thunderbird Account Hub, and manual folder sorting support. Thunderbird 140 also brings experimental support for Microsoft Exchange account setup.

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Thunderbird 140 also adds an Export for Mobile option to generate a QR code for quickly transferring account settings and credentials to the Thunderbird for Android app. Thunderbird 140 also brings many other bug fixes and enhancements.

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Downloads and more details on the Thunderbird 140 release via [3]Thunderbird.net .



[1] https://www.phoronix.com/image-viewer.php?id=2025&image=thunderbird_140_1_lrg

[2] https://www.phoronix.com/image-viewer.php?id=2025&image=thunderbird_140_2_lrg

[3] https://blog.thunderbird.net/2025/07/welcome-to-thunderbird-140-eclipse/