ChartJs Bubble Title on bubbles

How to add title above bubbles.

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<canvas id="bubble-chart" width="800" height="800"></canvas>

JavaScript

new Chart(document.getElementById("bubble-chart"), {
  type: 'bubble',
  data: {
    labels: "Africa",
    datasets: [{
      label: ["China"],
      backgroundColor: "rgba(255,221,50,0.2)",
      borderColor: "rgba(255,221,50,1)",
      title: "dataTitle1",
      data: [{
        x: 21269017,
        y: 5.245,
        r: 15
      }]
    }, {
      label: ["Denmark"],
      backgroundColor: "rgba(60,186,159,0.2)",
      borderColor: "rgba(60,186,159,1)",
      title: "dataTitle2",
      data: [{
        x: 258702,
        y: 7.526,
        r: 10
      }]
    }, {
      label: ["Germany"],
      backgroundColor: "rgba(0,0,0,0.2)",
      borderColor: "#000",
      title: "dataTitle3",
      data: [{
        x: 3979083,
        y: 6.994,
        r: 15
      }]
    }, {
      label: ["Japan"],
      backgroundColor: "rgba(193,46,12,0.2)",
      borderColor: "rgba(193,46,12,1)",
      title: "dataTitle4",
      data: [{
        x: 4931877,
        y: 5.921,
        r: 15
      }]
    }]
  },
  options: {
    title: {
      display: true,
      text: 'Predicted world population (millions) in 2050'
    },
    scales: {
      yAxes: [{
        scaleLabel: {
          display: true,
          labelString: "Happiness"
        }
      }],
      xAxes: [{
        scaleLabel: {
          display: true,
          labelString: "GDP (PPP)"
        }
      }]
    }
  }
});

Chart.plugins.register({
  afterDatasetsDraw: function(chart, easing) {
    var ctx = chart.ctx;

    chart.data.datasets.forEach(function(dataset, i) {
      var meta = chart.getDatasetMeta(i);
      if (meta.type == "bubble") { //exclude scatter
        meta.data.forEach(function(element, index) {
          // Draw the text in black, with the specified font
          ctx.fillStyle = 'rgb(0, 0, 0)';
          var fontSize = 13;
          var fontStyle = 'normal';
          var fontFamily = 'Helvetica Neue';
          ctx.font = Chart.helpers.fontString(fontSize, fontStyle, fontFamily);

          // Just...