title: Highcharts 'Cannot read property tooltipOptions of null'
body: <p>If have the following highchart:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>statisticsChart = new Highcharts.Chart({
    chart: {
      renderTo: 'advertisements-graphic-chart',
      type: 'line'
    },
    title: {
      text: ''
    },
    plotOptions: {
      series: {
        connectNulls: true,
      }
    },
    tooltip: {
      formatter: function() {
        return "ceva";
      }
    },
    xAxis: {
      categories: []
    },
    yAxis: {
      title: {
        text: ''
      }
    },
    series: [{
      id: CHART_SERIES_IDS.ALL_PRINTS,
      name: "All prints",
      data: []
    }, {
      id: CHART_SERIES_IDS.ALL_VIEWS,
      name: "All views",
      data: []
    }, {
      id: CHART_SERIES_IDS.ALL_CLICKS,
      name: "All clicks",
      data: []
    }, {
      id: CHART_SERIES_IDS.MY_PRINTS,
      name: "My prints",
      data: []
    }, {
      id: CHART_SERIES_IDS.MY_VIEWS,
      name: "My views",
      data: []
    }, {
      id: CHART_SERIES_IDS.MY_CLICKS,
      name: "My clicks",
      data: []
    }, {
      id: CHART_SERIES_IDS.ADVERT_PRINTS,
      name: "Advert prints",
      data: []
    }, {
      id: CHART_SERIES_IDS.ADVERT_VIEWS,
      name: "Advert views",
      data: []
    }, {
      id: CHART_SERIES_IDS.ADVERT_CLICKS,
      name: "Advert clicks",
      data: []
    }, ]
  });</code></pre>
  </div>
  </div>
  </p>
  
  <p>at some point in time I do...</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>statisticsChart.get(CHART_SERIES_IDS.ALL_PRINTS).setData(all_prints);
  statisticsChart.get(CHART_SERIES_IDS.ALL_VIEWS).setData(all_views);
  statisticsChart.get(CHART_SERIES_IDS.ALL_CLICKS).setData(all_clicks);
  statisticsChart.get(CHART_SERIES_IDS.MY_PRINTS).setData(my_prints);
  statisticsChart.get(CHART_SERIES_IDS.MY_VIEWS).setData(my_views);
  statisticsChart.get(CHART_SERIES_IDS.MY_CLICKS).setData(my_clicks);
  statisticsChart.get(CHART_SERIES_IDS.ADVERT_PRINTS).setData(advert_prints);
  statisticsChart.get(CHART_SERIES_IDS.ADVERT_VIEWS).setData(advert_views);
  statisticsChart.get(CHART_SERIES_IDS.ADVERT_CLICKS).setData(advert_clicks);
  
  statisticsChart.redraw();</code></pre>
  </div>
  </div>
  </p>
  
  <p>but after this point my console keeps shouting:</p>
  
  <p><code>Uncaught TypeError: Cannot read property 'tooltipOptions' of null</code></p>
  
  <p>..printing it for tens of times each time I move my mouse inside the chart area.</p>
  
  <p>I've tried debuggin the <code>tooltip.formatter</code> and <code>tooltip.pointFormatter</code> functions but it does not even get to those when that error shouts.</p>