Today we are rolling out a new Windows 10 preview build with significant Internet Explorer interoperability updates. In line with our commitment to interoperability and compatibility, this update includes over 2000 fixes for interoperability issues, support for 19 new platform features, and our new architecture for advancing interoperability and compatibility. We’re excited to be sharing this work at such an early stage in our development process and we look forward to hearing your feedback. We're also rolling out this preview build to users of our new RemoteIE service, available for Windows, Mac OS X, and other platforms.

Introducing the “living” Edge document mode

The cornerstone of this update to IE is the “Edge” mode platform—a new document mode designed with interoperability at its core. With this mode, we’re applying the highly successful interoperability strategy of Windows Phone 8.1 Update to Windows 10.

As we announced in August 2013, we are deprecating document modes as of IE11. With our latest platform updates, the need for legacy document modes is primarily limited to Enterprise legacy web apps. With new architectural changes, these legacy document modes will be isolated from changes in the “living” Edge mode, which will help to guarantee a much higher level of compatibility for customers who depend on those modes and help us move even faster on improvements in Edge. The next major version of IE will still honor document modes served by intranet sites, sites on the Compatibility View list, and when used with Enterprise Mode only.

Public Internet sites will be rendered with the new Edge mode platform (ignoring X-UA-Compatible). It is our goal that Edge is the "living" document mode from here out and no further document modes will be introduced going forward. We need your help in testing this new mode so we are enabling it on by default for a small percentage of the Windows Insider user base and those of you that manually select the mode (see below).

Edge mode introduces an interoperable UA string designed to get today’s modern Web content, and to avoid old IE-only content. We’ve also spent a lot of time ensuring that the IE platform behaves like modern Web content expects.

In cases where these changes necessarily differ from standards, we’re following through with standards bodies and other browsers to update specs and implementations to reflect the interoperable behavior.