Chicago (IL) - Mozilla plans to hold its launch party for Firefox 3.0 tomorrow. Behind the frenzy, the developers are already preparing Firefox 3.1, the first minor upgrade for the browser scheduled for a release late this year. The first alpha version of the browser, code-named Shiretoko, surfaced today.

Shiretoko became available earlier today on Mozilla’s FTP server in versions for Linux, Mac and 32-bit Windows. According to Firefox developer Mike Beltzner, the upgrade will be running on the Gecko 1.9.1, engine and include features that didn’t make it in time into Firefox 3.0. These features will include window previews for CTRL+Tab feature as well as "Tag Autocomplete, Advanced Search UI, Bulk tagging support, Download History integration, Enhanced compatibility checking during upgrades and coherent startup/shutdown prefs/behaviours."

The browser carries the version number 3.1a1preinstalls and is installed under the "Minefield" name, which is Mozilla’s description for full trunk builds that are used by the organization’s testing community. Minefield users can file bug reports and submit crash reports.

Firefox 3 is scheduled for release tomorrow. So far, 1.36 million people have signed up to download the browser on its first day of availability.

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