<style>* { display: table; }</style>
<body>Test passes if it does not crash.</body>
<script>
if (window.testRunner)
    testRunner.dumpAsText();

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range = document.createRange();
range.selectNodeContents(document.body);
window.getSelection().addRange(range);
document.execCommand("FormatBlock", false, "h1");
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