Once among the fastest, Firefox's TraceMonkey JavaScript engine has slipped behind the performance offered by Chrome, Opera, and Safari. In hopes of propelling Firefox into the lead, Mozilla is developing a new JavaScript engine called JägerMonkey.

To accomplish the feat, the outfit is borrowing some code from Apple's WebKit project. Mozilla aims to meld the powerful optimization techniques of TraceMonkey with the efficient native code generator of Apple's JSCore engine. An implementation that could regain lost ground for Firefox in the JavaScript speed wars.

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