ChartJs in endless loop

Question

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>

Answer 1

This seems to happen because chart.js does not like the small amount of margin, if you increase it it works fine or if you put a surrounding div around it and put the margin on that it also seems to work fine:

var initData = {
  type: "polarArea",
  data: {
    labels: ['a', 'b'],
    datasets: [{
      data: [2, 4]
    }]
  },
  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>
  <div style="margin: 0.5em;">
    <canvas style="width: 100%; height: 20em;" id="test"></canvas>
  </div>
</div>

Edit:
I was not totally correct with the larger size of margin fixes it, it so happend to just be a correct number.

Chart.js does need a dedicated container around the chart for the margin to function properly as described in the docs here