code: function(event) {
          // IE9 implements 'input' event it's so fubared that we rather pretend that it doesn't have
          // it. In particular the event is not fired when backspace or delete key are pressed or
          // when cut operation is performed.
          // IE10+ implements 'input' event but it erroneously fires under various situations,
          // e.g. when placeholder changes, or a form is focused.
          if (event === 'input' && msie <= 11) return false;
  
          if (isUndefined(eventSupport[event])) {
            var divElm = document.createElement('div');
            eventSupport[event] = 'on' + event in divElm;
          }
  
          return eventSupport[event];
        }
docs: jshint +W018