HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>safe release helper</title>
  <style>
    #knob {
      width: 64px;
      height: 64px;
      background: #16a34a;
      border-radius: 50%;
      cursor: grab;
      touch-action: none;
      user-select: none;
      margin: 16px 0;
    }
  </style>
</head>
<body>
  <div id="knob"></div>
  <pre id="out">Press and release the knob</pre>
  <script>
    function safeRelease(el, pointerId) {
      if (el.hasPointerCapture(pointerId)) {
        el.releasePointerCapture(pointerId);
        return true;
      }
      return false;
    }
    var knob = document.getElementById("knob");
    var out = document.getElementById("out");
    knob.addEventListener("pointerdown", function (ev) {
      knob.setPointerCapture(ev.pointerId);
    });
    knob.addEventListener("pointerup", function (ev) {
      out.textContent = "released: " + safeRelease(knob, ev.pointerId);
    });
  </script>
</body>
</html>

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Element.releasePointerCapture — safe release helper (Try It)