ChartJs in endless loop

I’ve got a just-created empty chart.js chart and it stucks in an animated endless loop. Why? What am I doing wrong?

var initData=
{
  type: "polarArea",
  data: {datasets:[]},
  options: {
    plugins: {},
    responsive: true,
    maintainAspectRatio: false,
    scales: {
      r: {}
    }
  }
};

var context = document.getElementById('test').getContext('2d');
var chart = new Chart(context, initData);
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/chart.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]"></script>
<div><canvas style="margin: 0.5em; width: 100%; height: 20em" id="test"></canvas></div>