FullCalendar: Event with tooltips/custom event attributes

HTML

<link rel="stylesheet" href="http://arshaw.com/js/fullcalendar-1.5.3/fullcalendar/fullcalendar.css">
<script src="http://www.arshaw.com/js/fullcalendar-1.5.3/fullcalendar/fullcalendar.min.js"></script>
<script src="http://davis-design.de/marktadresse/layout/js/foundation-datapicker.js"></script>
<link rel="stylesheet" href="http://davis-design.de/marktadresse/layout/css/foundation-datapicker.css">
</br>
    
Datepicker :<input type="text" id="endDate" name="end_datum" class="input_text" value=""></br></br></br></br>

<div style="border:solid 2px red;">
	<div id='calendar'></div>
</div>
<div class="tag hide" id="cal-info">

</div>

CSS

.tag{
  background-color:#000;
  color:#fff;
  padding:3px;
  max-height:60px;
  overflow: visible;  
  position: fixed;
  z-index:999;
}
.tag:after {
  content: "";
  border-top: 16px solid red;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  position: absolute;
  bottom: -16px;
  left: calc(50% - 8px);
}
.fc-border-separate thead.sticky{
	width: 100%;
	position: fixed;
	top:0px;
	left:0px;
	display:table;
	background: #fff;
}

JavaScript

var nowTemp = new Date();
      var now = new Date(nowTemp.getFullYear(), nowTemp.getMonth(), nowTemp.getDate(), 0, 0, 0, 0);
      var checkin = jQuery('#startDate').fdatepicker({
          format: "dd.mm.yyyy", 
      }).data('datepicker');
      var checkout = jQuery('#endDate').fdatepicker({
          format: "dd.mm.yyyy", 
      }).on('changeDate', function (ev) {
            
          }).data('datepicker');

          
  
  
  $(document).ready(function() {

    var date = new Date();
    var d = date.getDate();
    var m = date.getMonth();
    var y = date.getFullYear();

    var events_array = [
        {
        title: 'Test1',
        start: new Date(2012, 8, 20),
        tip: 'Personal tip 1'},
    {
        title: 'Test2',
        start: new Date(2012, 8, 21),
        tip: 'Personal tip 2'}
    ];

    $('#calendar').fullCalendar({
        header: {
            left: 'prev,next today',
            center: 'title',
            right: 'month,agendaWeek,agendaDay'
        },
        selectable: true,
        events: events_array,
        eventRender: function(event, element) {
            element.attr('title', event.tip);
        }
    });
});

$(".fc-header-left").hide();
$(".fc-header-right").hide();

  $(window).scroll(function() {
    if ($(this).scrollTop() > 1){  
        $('.fc-border-separate thead').addClass("sticky");
    }
    else{
        $('.fc-border-separate thead').removeClass("sticky");
    }
    });