The first developer milestone of the next release of Firefox - code named Shiretoko Alpha 1 - is now available for download. Shiretoko is built on pre-release version of the Gecko 1.9.1 platform, which forms the core of rich internet applications such as Firefox. Please note that this release is intended for developers and testers only.

This Alpha of Shiretoko / Gecko 1.9.1 introduces several new features:
Web standards improvements in the Gecko layout engine
Text API for the element
Support for using border images
Support for JavaScript query selectors
Several improvements to the Smart Location Bar
A new tab switching behavior

Anyone interested in Shiretoko should read the release notes, as well as the “Firefox 3.1 For Developers” article on the Mozilla Developer Center before downloading. Please use the following links to download Shiretoko:
Windows: Shiretoko Alpha 1 Setup.exe
http://download.mozilla.org/?product=shiretoko-alpha1&os=win&lang=en-US
Mac OS X: Shiretoko Alpha 1.dmg
http://download.mozilla.org/?product=shiretoko-alpha1&os=osx&lang=en-US
Linux: shiretoko-alpha1.tar.bz2
http://download.mozilla.org/?product=shiretoko-alpha1&os=linux&lang=en-US
We would appreciate hearing about any feedback you have, or any bugs you may find.