<!doctype html>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
A
<script>
addEventListener("load", () => {
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  textarea.addEventListener("focusin", onFocusIn);
  textarea.select();
  document.execCommand("outdent");
});

function onFocusIn() {
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    window.find("AA");
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  document.designMode = "on";
  document.execCommand("selectAll");
  document.execCommand("indent");
  document.designMode = "on";
}
</script>
<fieldset>
<textarea></textarea>
AA
</fieldset>
<marquee id="b"></marquee>
<blockquote contenteditable="true"></blockquote>
</body>
</html>
