Google Chrome different browsers on Google's own suite, commenting on Chrome's "decimating" of the other browsers, but he questioned whether Google's suite was representative of real programs. He stated that Firefox 3.0 performed poorly on recursion-intensive benchmarks, such as those of Google, because the Mozilla team had not implemented recursion-tracing yet. Two weeks after Chrome's launch in 2008, the WebKit team announced a new JavaScript engine, SquirrelFish Extreme, citing a 36% speed improvement over Chrome's V8 engine. Like most major web browsers, Chrome uses DNS prefetching to speed up website lookups, as do other browsers like Firefox, Safari, Internet Explorer (called DNS
Internet Explorer 9 URLs, and Application Reputation to detect untrustworthy executables—provides the best socially engineered malware blocking of any stable browser version. Internet Explorer 9 blocked 92 percent of malware with its URL-based filtering, and 100 percent with Application-based filtering enabled. Internet Explorer 8, in second place, blocked 90 percent of malware. Tied for third place were Safari 5, Chrome 10, and Firefox 4, each blocking just 13 percent. Bringing up the rear was Opera 11, blocking just 5 percent of malware. Due to technical improvements of the browser, the Internet Explorer developer team decided to change the user agent (UA) string. The