Mozilla slams Google's Chrome Frame as 'browser soup'

But Chrome Frame's biggest problem, said Baker, is that it cedes control to the site, not the person surfing. And that will just confuse users.

"For many people, Chrome Frame will make the Web even more unknowable and confusing," Baker said. "Image you download Chrome Frame. You go to a Web site. What rendering engine do you end up using? That depends on the Web site now, not on you."

Microsoft took a different tack when it slammed Google for releasing Chrome Frame. The plug-in, claimed Microsoft, not only doubles the risk of attack -- users have to worry about vulnerabilities in both IE and Chrome -- but also breaks several features in its browser, including the private browsing mode.

Mike Shaver, Mozilla's vice president of engineering, weighed in yesterday alongside Baker, but also gave Google some advice.

"The user's understanding of the Web's security model and the behavior of their browser is seriously hindered by delegating the choice of software to the developers of individual sites they visit," Shaver said. "It is a problem that we have seen repeatedly with other stack plug-ins like Flash, Silverlight and Java, and not one that I think we need to see replayed again under the banner of HTML 5.

"It would be better for the Web if developers who want to use the Chrome Frame snippet simply told users that their site worked better in Chrome, and instructed them on how to install it," Shaver added.

He also panned Chrome Frame for some of the same reasons as Microsoft, but added several features "bricked" by the plug-in to the list, including IE8's Accelerators and accessibility tools.

Google's approach to solving the outdated browser problem is the path to madness, Baker concluded.

"Imagine having the Google browser-within-a-browser for some sites, the Facebook browser-within-a-browser for Facebook Connect sites, the Apple variant for iTunes, the mobile-carrier variant for your mobile sites," said Baker. "Each browser-within-a-browser variant will have its own feature set, its own quirks, and its own security problems. The result is a sort of browser-soup, where ... the Web is less knowable, less understandable and certainly less manageable."

The Chrome Frame plug-in works with IE6, IE7 and IE8 on Windows XP and Windows Vista. It's available from Google's site as a free download.

Google did not immediately reply to a request for a reaction to Mozilla's criticisms of Chrome Frame.

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