which uses Just-in-time compilation to execute JavaScript as native code. In mid-September 2011, the Acid3 test was revised to remove a few "antiquated and unusual" tests, and as a result, IE9 now passes the test with a score of 100/100.

At MIX 10, the first Internet Explorer 9 Platform Preview was released, which featured support for CSS3 and SVG, a new JavaScript engine called Chakra,