HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>ariaMultiLine MDN</title>
</head>
<body>
  <div id="txtboxMultilineLabel">Enter the tags for the article</div>
  <div
    role="textbox"
    id="txtBoxInput"
    contenteditable="true"
    aria-multiline="true"
    aria-labelledby="txtboxMultilineLabel"
    aria-required="true"
  ></div>
  <pre id="out"></pre>
  <script>
    var el = document.getElementById("txtBoxInput");
    var lines = [el.ariaMultiLine];
    el.ariaMultiLine = "false";
    lines.push(el.ariaMultiLine);
    document.getElementById("out").textContent = lines.join("\n");
  </script>
</body>
</html>

Lines: 0 | Characters: 0

Live Preview Auto-refresh on Run

Element.ariaMultiLine — MDN set false (Try It)