The Mozilla Project developers have announced the release of the first alpha for version 3.3 of Thunderbird, code named "Miramar". According to Mozilla Messaging Product Manager Rafael Ebron, Miramar Alpha 1 is aimed at "testers, extension developers, and other friends who are curious to follow the development of the next release of Thunderbird".

Like Firefox 4, which is also currently in development, the early version of Mozilla's next generation open source email client is based on version 2.0 of the Gecko rendering platform – the Thunderbird 3.1 and Firefox 3.6 branches use Gecko 1.9.2 – and features a new Add-ons Manager and extension management API. The developers note that the user interface for the new Add-ons Manager will be changed before the final release. The alpha release includes support for 32 and 64-bit Mac OS X builds, but drops support for older PowerPC processor based Macs. Other changes include user interface fixes for Windows 7 and Vista, and platform fixes for more than 190 bugs – a full list of bug fixes can be found on Bugzilla.



Thunderbird 3.3 Alpha 1 "Miramar" on Mac OS X. As with all development releases, use in production environments and on mission critical systems is not advised. Additionally, installing Miramar Alpha 1 may overwrite existing installations of Thunderbird on Linux systems. Users testing the release are encouraged to provide feedback and report any bugs that they encounter.

More details about the preview release, including a list of known issues, can be found in the release notes and on the Miramar Alpha 1 page. Thunderbird 3.3 Alpha 1 is available to download for Windows, Mac OS X and Linux in English (US) only. The developers say that future Beta and Release Candidate versions will be made available in more languages.

Thunderbird binaries are released under the Mozilla Thunderbird End-User Software License Agreement and the source code is released under disjunctive tri-licensing that includes the Mozilla Public Licence, GPLv2 and LGPLv2.1. The latest stable release of Thunderbird is version 3.1.6

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(crve)