"This is the last planned security and stability release for Firefox 3.5," said Christian Legnitto, who overseas Firefox releases. "All users are encouraged to upgrade to Firefox 4."
The support expiration for Firefox 3.5 will affect a minority of Mozilla's users: As of the end of March, just 1.7% of all users worldwide were running the browser, according to statistics from Web metrics company Net Application.
Users can update to Firefox 4.0.1 by downloading the new edition -- which runs on Windows, Mac and Linux -- or by selecting "Check for Updates" from the Help menu in the browser. Firefox 3.6 and 3.5 users can obtain their newest versions with the update tool.
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