Microsoft has confirmed that the new EdgeHTML.dll rendering engine for Internet Explorer is being used in the newly launched Windows 10 techical preview for phones. The new engine is already being used in the Windows 10 preview for desktops.
"The new rendering engine will be used for all web pages loaded in the browser on Windows 10 phones. Like on PCs, "x-ua-compatible" tags will no longer be supported to force older compatibility document modes. This ensures that sites on the mobile web will always get the latest, most interoperable engine."
The company also went over some of the other features that have been put into this first Windows 10 for phones preview release in terms of its support of web platforms:
"For multiple releases, we've been committed to shipping a unified web platform for Windows devices across all form factors and screen sizes. As a result, the new Windows 10 web platform on phones comes with the same interoperability improvements, new features, increased performance, and improved standards support we've been previewing on PCs for the last several months. Going forward, you can expect to see an even tighter coordination of new web platform update availability on PCs and phones."
"Windows 10 introduces a new user agent string for phones – based on our new desktop user agent string – designed to get the most modern, interoperable content for the mobile web. Sites inspecting the user agent string for analytics should be aware of the new string, but we continue to believe that feature detection rather than browser detection is the best solution for web developers writing interoperable content."
The new web browser that Microsoft is currently working on, under the code name Project Spartan, is not part of this first Windows 10 preview for phones. However, it will use the same rendering engine that IE currently has in this build. Project Spartan will replace IE entirely in a future preview build of Windows 10 for phones.