Google yesterday shifted Chrome 6 into beta, a move that puts the browser one step closer to a stable release. Chrome 6, specifically version 6.0.472.33, includes speed and stability improvements, Google said, as well as a tweaked user interface and enhanced synchronisation of bookmarks, passwords and other data among machines running the browser.

In a post to the Chrome blog, Google engineer James Hawkins claimed that Chrome 6 is approximately 15% faster in rendering JavaScript than its predecessor.

The browser, already known for a sparse design that some rivals have started to mimic, also received a minor makeover. Some elements were shifted, the bookmark icon has been moved to the right of the address bar, and others were compressed. Chrome now sports a single menu, down from two earlier, that hides all but the most basic browsing commands, such as page forward, page backward and page reload.

Hawkins also touted Autofill, a feature enabled by default in Chrome 6's beta, saying in a supporting video that the timesaver automatically enters the user's name, address, phone number and email address in website forms. Autofill will also save credit card numbers to the browser for online purchases, there, however, Chrome requires the user to confirm the saving of each credit card number.

Autofill isn't new, other browsers have similar tools, but its security has recently come under attack. Last month, Jeremiah Grossman, founder and CTO of WhiteHat Security, showed how hackers could mine names, mailing addresses, email addresses and workplaces from Apple's Safari because the browser turns on its autofill feature by default, and links it to the user's entry in the address book on their Mac or PC.

Apple patched Safari's Autofill flaw the day before Grossman demonstrated his data-mining attack at the Black Hat security conference. During his presentation, Grossman also showed how to pilfer autofill data from Internet Explorer 6 (IE6) and IE7.

Yesterday, Grossman said he suspected, but hadn't confirmed, that the same tactics would not work against Chrome 6. However, other attack techniques might be able to pillage Chrome for the saved credit card numbers, he added. "[But] a lot more testing would have to be done to confirm [that]," Grossman said. "For now a lot of this is just speculation."

Google 6 also boasts enhanced sync that lets users synchronise extensions and autofill entries between copies of the browser on different machines. Previously, the tool synced bookmarks, passwords, preferences and themes only. Credit card information isn't included in the autofill sync.

Earlier this week, Google updated the "stable" version of Chrome, the most polished production quality edition, to update the bundled copy of Flash Player. Several months ago, Google and Adobe partnered to tuck the popular plug-in inside the browser installer, and Google said it would regularly refresh the plug-in using Chrome's silent update service.

Adobe patched six critical vulnerabilities in Flash Player Tuesday. Chrome's stable update of Wednesday provided users with the same version 10.1.82.76 that Adobe released the day before.

Chrome 6 beta can be downloaded from Google's website for Windows, Mac OS X and Linux.