title: Invoke rest service when mouseenter the element on the page
body: <p>I have a element on my page. When i mouseenter the element, invoke my rest service, get data from this service and display a tooltip with this data. When mouse leave the element tooltip hidding. Everythings work fine in Chrome, Firefox and Opera, but not in Internet Explorer.</p>
  
  <pre><code>jQuery(document).ready(function() {
      showAndHideTooltip();
  });
  
  showAndHideTooltip = function() {
      jQuery(document).on({
          mouseenter: function () {
              console.log("Enter start");
              jQuery(".tooltip").stop(
                      true, true).delay(1000).fadeIn(500);
              getData();
              console.log("Enter end");
          },
          mouseleave: function () {
              console.log("Leave start");
              jQuery(".tooltip").stop(
                      true, true).delay(1000).fadeOut(500);
              console.log("Leave end");
          }
      }, ".element");
  }
  
  getData = function() {
      jQuery.ajax({
      url : 'rest/data/',
      type : 'POST',
      dataType : 'json',
      async: false,
      success : function(data) {
          console.log("Success");
      },
      error : function(data) {
          console.log("Error: Get data");
      }
  })
  </code></pre>
  
  <p>When I log all the events I get the following logs:</p>
  
  <pre><code>Enter start
  Success
  Enter end
  Leave start
  Leave end
  </code></pre>
  
  <p>So everything correctly, but not in IE. When I only one enter the element in Internet Explorer.
  Example logs, when I only one enter on my element: </p>
  
  <pre><code>Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  Leave start
  Leave end
  Enter start
  Success
  Enter end
  </code></pre>
  
  <p>So I get repeatedly invokes in Internet Explorer, when in others browsers I get only one invoke. Moreover in the last invoke mouse leave event not execute and tooltip not disappear.</p>
  
  <p>When I remove invoke rest service in my event, everything work good in all browsers.</p>
  
  <p>I think problem is in set <code>async: false</code> in my ajax request, but when I change false to true, above problem see in Internet Explorer and Firefox too...</p>
  
  <p>Anyone know how to fix this problem? How to correctly handle a call to rest service in the mouse event?</p>