InternetExplorer 4 is the fourth major version ofInternetExplorer, released in September 1997 for Microsoft Windows, Mac OS, Solaris, and HP-UX. It was the first version ofInternetExplorer to use the Trident web engine. Hackers used Edge’s IE mode to bypass security and take control of devices.The exploitation of Microsoft Edge’s InternetExplorer mode underscores the evolving sophistication of cyber threats and the enduring danger of legacy software components. What Version ofInternetExplorer (IE) Do I … InternetExplorer mode in Edge should be understood as a temporary solution, not a permanent solution. The sooner you plan to modernize applications that still require IE Mode, the lower the risk and maintenance costs will be. Starting with IE8, InternetExplorer introduced a new “document mode” with every release. These document modes could be requested via the x-ua-compatible header to put the browser into a mode which emulates legacy versions. After a period of inactivity, InternetExplorer became the bane of our existence. Microsoft has since recommitted to their browser but the fact remains that sometimes modern InternetExplorer is lagging just a bit behind WebKit-based browsers and Firefox. For such cases, Edge maintains InternetExplorer mode to ensure critical operations remain functional during the process of modernization. However, IE’s underlying design lacks the hardened, multi-process architecture and sandboxing techniques of Chromium.