simple_textarea.html | Explore in Territory

<html>
  <body>
    <textarea id="text_id"></textarea>
    <div id="text_events"></div>
    <script>
      document.getElementById('text_id').addEventListener('input', (e) => {
        text_events.innerText += e.data + ';' + e.inputType + ';' + e.isComposing + '\n';
      });
    </script>
  </body>
</html>

chromium/chrome/test/data/textinput/simple_textarea.html