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<html lang="en">
<head>
  <meta charset="utf-8">
  <title>lastStyleSheetSet MDN</title>
</head>
<body>
  <pre id="out"></pre>
  <script>
    var lastSheetSet = "lastStyleSheetSet" in document
      ? document.lastStyleSheetSet
      : null;
    if (!lastSheetSet) {
      lastSheetSet = "Style sheet not yet changed";
    }
    document.getElementById("out").textContent = lastSheetSet;
  </script>
</body>
</html>

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