The Mozilla Foundation has unveiled the most complete preview version yet of its stand-alone email application.
The release comes only weeks after the launch of its Firefox browser version 1.0, and is part of the open source software project's continuing efforts to chip away market share from Microsoft's dominate Internet Explorer.
The release candidate of Thunderbird 1.0 email management software, launched on Wednesday, is being positioned as similar to Microsoft's free end-user application Outlook Express but without the user hassles of dealing with advertisements and spam.
Before the official release of Thunderbird 1.0, slated for 7 December, the group is offering the preview version of the free client for last-minute testing. Based on the Mozilla codebase, Thunderbird 1.0 works with most operating systems including Windows, Linux and Macintosh.
The Mozilla Foundation has said in the past that it aims to capture between 10 percent and 12 percent of the web browser market by the end of next year. It has already been able to eke out a 3 percent share through its preview versions of Firefox, though Microsoft's IE continues to hoard as much as 95 percent of the market, according to figures from WebSideStory.
Thunderbird is part of that overall effort, although Outlook Express is far from Mozilla's only competition among email clients, with Yahoo (Yahoo Mail), Google (Gmail) and Microsoft (Hotmail) all offering popular and free web-based email services.
Mozilla believes it can woo users over to Thunderbird with features such as the ability to choose between three message views and to customise toolbar buttons, an integrated Usenet newsgroup reader, and security features such as not allowing scripts to run by default.
The Mozilla Foundation is a nonprofit organisation created in July 2003 to support the Mozilla open source software project. Mozilla was originally created at Netscape Communications in 1998, which was since acquired by media conglomerate Time Warner.
The new Thunderbird release candidate can be downloaded online.