While Microsoft is laboring to produce the second Beta of Internet Explorer 8, Mozilla not only wrapped up Firefox 3.0 formerly codenamed Grand Paradiso, but also moved onward with the development of Firefox 3.1 codenamed Shiretoko. With the earliest builds of Shiretoko debuting hot on the heels of Firefox 3.0's launch, Mozilla unveiled Firefox 3.1 Alpha 1 at the end of the past week, making the development milestone available for download and starting on building Alpha 2. The first Alpha of Shiretoko is by no means feature complete, far from it in fact, but it will give testers a taste of what's coming in the final release.

Mike Beltzner, Mozilla User Experience Lead managed to detail some of the new features delivered by Shiretoko / Gecko 1.9.1 Alpha 1 including "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 and a new tab switching behavior". Mozilla warned that the modifications introduced in Firefox 3.1 Alpha 1 in comparison with Firefox 3.0 would impact web and platform compatibility in certain scenarios.

However, as far as the end user experience is concerned, two of the new features take center stage. One is related to the new tab switching behavior via the Tab + Ctrl hotkeys. The new default model for switching between the current and previous tabs involves an overlay menu featuring tab thumbnails and not just the classic move to the next tab on the right. Additionally, the tab thumbnails are ordered in accordance with the tabs most recently viewed by the end user, and not by their actual positioning. Firefox 3.1 permits the configuring of this feature via "about:config", like increasing the number of tab thumbnails displayed through modifying the value associated with browser.ctrlTab.previewsCount or by going back to the old behavior by setting the browser.ctrlTab.mostRecentlyUsed to false.

Mozilla is also advancing the Smart Location Bar, enabling greater flexibility for users when performing queries. What Firefox 3.1 Alpha 1 brings is the possibility to limit the location bar autocomplete suggestions to certain just information stored by the browser in bookmarks, tags, history, page titles or addresses. In this regard, "+" restricts results just to tags, "^" to history, "*" to bookmarks, "@" to the URLs, "#" to titles.

"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," Beltzner said.

Firefox 3.1 Alpha 1 for Windows is available for download here.
Firefox 3.1 Alpha 1 for Linux is available for download here.
Firefox 3.1 Alpha 1 for Mac OS X is available for download here.