add id jquery

JavaScript
$('element').attr('id', 'value');<h2>Greetings</h2>
<div class="container">
  <div class="inner">
    Hello
    <p>Test</p>
  </div>
  <div class="inner">
    Goodbye
    <p>Test</p>
  </div>
</div>
<div class="container">
  <div class="inner">Hello</div>
  <div class="inner">Goodbye</div>
  <h2>Greetings</h2>
</div>
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>append demo</title>
  <style>
  p {
    background: yellow;
  }
  </style>
  <script src="https://code.jquery.com/jquery-3.5.0.js"></script>
</head>
<body>
 
<p>I would like to say: </p>
 
<script>
$( "p" ).append( document.createTextNode( "Hello" ) );
</script>
 
</body>
</html>

Source

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