Internet Explorer 10 compatibility mode and Resource Timing

When a page specifies IE8 compatibility mode, via:

<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE8"/>

it seems the window.performance object in IE10 on Windows 7/8 no longer
contains Resource Timing objects and methods.  It /does/ contain the
Navigation Timing objects (which wasn't available in IE8, which makes this
even stranger).  Is this expected behavior?  If so, is there a way to
force IE10 to give up its Resource Timing data even when EmulateIE8 is

To see this in action on a real-world site, go to and
open up the F12 tools.



Received on Friday, 3 May 2013 19:43:28 UTC