 In particular, it makes Firefox 3 the first official release of a Mozilla browser to pass the Acid2 test, a standards-compliance test for web-page rendering.It also receives a better score on the Acid3 test than Firefox 2.Some of the new features are defined in the WHATWG HTML 5 specification, such as support for web-based protocol handlers, a native implementation of the codice_1 method, support for safe message-passing with codice_2, and support for offline web applications.