text: (function(){
      Modernizr.addTest('customfilter', function () {
  
          var prop = 'filter';
          var prefixedProp = ['WebkitFilter', 'MozFilter', 'msFilter', 'OFilter', 'filter'];
          var prefixCSS = ['-webkit-filter', '-moz-filter', '-ms-filter', '-o-filter', 'filter'];
          var val = 'custom(url(data:text/plain;base64,))';
          var computedStyle;
  
          for(var i = 0, len = prefixCSS.length; i < len; i++) {
              Modernizr.testStyles('#modernizr { ' + prefixCSS[i] + ': ' + val + '; }', function (el, rule) {
                  computedStyle = window.getComputedStyle ? getComputedStyle(el, null).getPropertyValue(prefixCSS[i]) : '';
              });
              if(computedStyle && computedStyle.indexOf('custom') === 0) {
                  Modernizr.__prefixedFilter = prefixedProp[i];
                  return true;
              }
          }
          return false;
      });
  }());
  