Thunderbird 17 arrives with an Extended Support Release
Version 17 of Mozilla's Thunderbird news and email client has now arrived with an Extended Support Release forked for qualification in Mozilla's ESR process. The release itself has minor changes to the user interface and the developers will focus on continuing to provide security updates and bug fixes as Mozilla has ended Thunderbird's feature development to concentrate on other projects. Other developers with an interest in Thunderbird will, though, be able to submit feature changes to the application in future and the way is potentially open for enhanced releases of Thunderbird.
The latest Thunderbird release includes a new button in the top right corner of the application. Simply called the Menu Button, it replicates the application's Menu Bar in a drop down menu and offers users another option to customise the program's user interface (UI). On Windows, for new users, the Menu Button is used by default and the Menu Bar is automatically hidden, while on Mac OS X, as the Menu Bar is always visible. Another UI change that only affects Windows users is that, for them, tabs are now drawn in the title bar.
The new version also addresses a number of bugs found in the 16.x branch which caused it to spell check parts of words and repeatedly download emails when using IMAP. Like version 17 of Mozilla's Firefox web browser, Thunderbird 17 no longer supports systems running Mac OS X 10.5 Leopard. The developers have also addressed a total of 12 security vulnerabilities, five of which are rated as "Critical" by Mozilla.
Further information about the update, including a full list of bug fixes, can be found in the release notes. Thunderbird 17.0 is available to download for Windows, Mac OS X and Linux from the project's site as is Thunderbird ESR 17.0. Source code and binaries for Thunderbird are released under the Mozilla Public Licence 2.0.
Note: This story has been updated to reflect the split between the mainline and ESR release.