TrifleJS serves as a headless browser tailored for automated testing, leveraging the .NET WebBrowser class along with the V8 JavaScript engine to replicate environments akin to Internet Explorer. Modeled after PhantomJS, its API provides a sense of familiarity for users accustomed to that framework. It accommodates multiple versions of Internet Explorer, enabling emulation of IE7, IE8, and IE9, dictated by the version installed on the system. Developers are empowered to run scripts through the command line while specifying which version of Internet Explorer they wish to emulate. Additionally, TrifleJS features an interactive mode (REPL) that facilitates the debugging and testing of JavaScript code, enhancing the overall development experience. This flexibility makes it a valuable tool for developers looking to ensure compatibility across different Internet Explorer environments.