ark="a">notset</p>
    <script>
      const p1 = document.getElementById('1');
      test(p1.isConnected, 'p#1 connected');
      test(p1.innerText === 'notset', 'p#1 data not set');

      data.a = 'set';
      test(p1.innerText === 'set', 'p#1 data set');

      data.a = 'changed';
      test(p1.innerText === 'changed', 'p#1 data changed');

      delete data.a;
      test(!p1.isConnected, 'p#1 not connected');
    </script>

    <template name="green-p">
      <p style="color: green">
        <slot />
  