IE11 compatibility changes

[This documentation is preliminary and is subject to change.]

Changes to Internet Explorer 11 are designed to better comply with broader industry standards, provide consistency with modern browsers, and to improve performance and reliability.

This section describes features that operate differently in IE11 from earlier versions and identifies things that may require changes to sites and apps built to support earlier versions of the browser.

Unless otherwise specified, the changes in this section apply to IE11 edge mode and interoperable quirks mode in IE11.

Note  You may be able to use legacy document modes to emulate the behavior of earlier versions. if you do this, keep in mind it's a temporary solution at best. Starting with IE11, document modes are considered deprecated and might not be supported in any future versions of the browser. For best results, update your sites and apps to use features and techniques supported by industry standards and multiple browsers.

In this section


Checkbox and radio button layout defaults

To provide better consistency with other browsers, the default values for a number of layout properties have changed for checkbox and radio button controls in IE11 edge mode.

Cross-browser plugin detection

Plug-in detection code can now be consistent between browsers and you don't need to provide special code for Internet Explorer.

CSS expressions no longer supported for the Internet zone

Starting with IE11, CSS expressions are no longer enabled for webpages loaded in the Internet zone.

Document modes are deprecated

Starting with IE11, document modes are considered deprecated and should not be used. Make sure to update ebpages and apps that require legacy document modes to support modern features, browsers, and devices.

Enhanced protected mode (EPM) is enabled by default

As of IE11, enhanced protected mode is enabled for Internet Explorer for the desktop. Update add-ins, Browser Helper Objects (BHOs), and applications using local HTML resources to support enhanced protected mode.

Flexible box ("Flexbox") layout updates

With IE11, you can update your sites to match the latest Flexbox standard and simplify cross-browser code.

Mutation observers

In IE11, web developers gain support for W3C DOM4 Mutation observers to help monitor which DOM mutations they need to observe and follow.

Pointer events updates

To comply with the Candidate Recommendation of the World Wide Web Consortium (W3C) Pointer Events specification, the IE11 implementation has changed slightly from that of Internet Explorer 10.

Pseudo hit testing is disabled in IE11 edge mode

To provide better compatibility with other browsers and a more consistent experience for all interaction events (including touch and zoom), pseudo hit testing is disabled in IE11 edge mode.

VBScript is no longer supported

As of IE11, VBScript is considered deprecated and should no longer be used as a scripting language for IE11.

Window event behavior has changed

In order to provide more consistency with industry standards and other popular browsers, behavior of window.event has changed in IE11.




Build date: 9/27/2013