Get your own website Result Size: 625 x 565
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<!DOCTYPE html>
<html>
<body>
Address:<br>
<textarea id="myTextarea" placeholder="Your address..">
</textarea>
<p>Click the button to change the placeholder text of the text area.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
  document.getElementById("myTextarea").placeholder = "Where do you live?";
}
</script>
</body>
</html>