Firefox 3.1 beta 1 delivers the fastest iteration of Mozilla's browser yet, although it takes a small tweak to activate the new JavaScript engine. It seems the new JavaScript engine, called TraceMonkey, is not turned on by default. To activate it, type "about:config" into the Smart Bar, then type "javascript.options.jit.content" into the filter. Double-click on the preference listed to change the boolean setting from "false" to "true." Close the window and you should notice an immediate improvement to the JavaScript rendering speed.
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