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<body>
<h1>HTML DOM Attributes</h1>
<h2>The isId Property</h2>
<p>Is the first attribute an id? The answer is:</p>
<p id="demo"></p>
<script>
const element = document.getElementById("demo");
const answer = element.attributes[0].isId;
element.innerHTML = answer;
</script>
<p>The isId property is no longer supported in any browsers.</p>
<p>The isId property always returns indefined.</p>
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