Some of the features expected to make the final version are already tucked into the browser but have been turned off by default. Among them are support for WebGL and hardware acceleration based on Windows Vista's and Windows 7's Direct2D, the same API (application programming interface) Microsoft uses to speed up Internet Explorer 9.
Mozilla has set an aggressive schedule for Firefox 4. In May, Beltzner said the company was shooting for a final by the end of November, with a solid release candidate in mid-October. Tuesday, he told users to expect beta updates every two to three weeks.
Firefox accounts for approximately 23.8 percent of all browsers in use, according to the most recent data from Web metrics company Net Applications. The browser peaked last November at 24.7 percent. In the same seven months, Google's Chrome nearly doubling its usage share, going from 3.9 percent to 7.2 percent.
Firefox 4 Beta 1 can be downloaded for Windows, Mac and Linux from Mozilla's site. At the moment, only an English-language version is available.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is email@example.com.
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