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<p>For <a href="https://bugs.webkit.org/show_bug.cgi?id=84891">Bug 84891</a> -
mfenced add/remove child confusion.</p>

<p>This test passes if the math element is changed to (x1y).</p>

<math>
  <mfenced id="mfenced" separators="12"></mfenced>
  <mi id="mi1">x</mi>
  <mi id="mi2">y</mi>
</math>

<script>
var mfenced = document.getElementById("mfenced");
var mi1 = document.getElementById("mi1"), mi2 = document.getElementById("mi2");
mfenced.appendChild(mi2);
mfenced.insertBefore(mi1, mi2);
</script>
</body>
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