Highchart not rendering the marker for first point in a live chart.

HTML

<script src="http://highcharts.com/js/testing.js"></script>
<div id="container" style="width: 450px; height: 300px"></div>

JavaScript

var dummyElement;
var chart = Highcharts.Chart({
    chart: {
        renderTo: 'container',
        events: {
            load: function() {
                var chart = this;
                var series = this.series[0];
                var data = series.data;
                setInterval(function() {
                    var shift = data.length > 10;
                    series.addPoint(Math.random() * 101, true, shift);
                    
                    if (document.documentMode === 8) {
                        if (dummyElement) {
                            dummyElement.destroy();
                        }
                        dummyElement = chart.renderer.path()
                            .add();
                    }
                }, 2000);
            }
        }
    },
    series: [{
        data: []
    }]
});