In IE11 if I/you visit (for viewport testing purposes) http://ryanve.com/lab/dimensions/ you can see that viewport dimensions across a number of the queries ie window, inner outer etc a wrong, just visit in Chrome and they show correct values.
I was using this script when I noticed and looked further into it:
var wi = $(window).width();
$("p.testp").text('Initial screen width: ' + wi + 'px.');
My screen is 2048, but is returning 2556 in IE11
Anyone? thanks P