Modernizr test for legacy IE Filters and Transitions (COMPLETELY UNTESTED!)

modernizr-ielegacyfilters.js

/*
    Modernizr test for legacy IE Filters and Transitions

    I haven't tested this with Modernizr! Just adapted my solution to look like 
    https://gist.github.com/farmdawgnation/2636061

    Needed because Filters and Transitions can be disabled under IE's security 
    settings ("Binary and Script Behaviors" under the "ActiveX controls and 
    plug-ins" category). This is often done on corporate windows installations 
    "for security reasons". They'll fail silently (or error if you try to access
    the element's filter collection in js). This setting also disables VML.

    See: 
    http://paintincode.blogspot.co.uk/2012/06/css-opacity-ie-filter-binary-and-script.html
*/
Modernizr.addTest('iefilters', function() {
    var supportsIEfilters = false, 
        el = document.body.appendChild(document.createElement("div")), 
        probe = 0;

    /* Try to set a filter on the div, then access the div's filters collection. 
       IE throws an error here if filters are disabled, so supportsIEfilters will
       remain false. */
    try {
        el.style.filter = "progid:DXImageTransform.Microsoft.Alpha(opacity=50)";
        probe = el.filters.length;
        supportsIEfilters = true;
    } catch (err) {
        /* In legacy IE, err will be "Unspecified error" if filters are disabled. 
           New browsers shouldn't have an el.filters so it'll be a reference 
           error (undefined). */
        /* console.log("Error: ", err); */
    }

    el.parentNode.removeChild(el);
    return supportsIEfilters;
});