Send chat message to active window

shopee_chat_send.js

window.InputEvent = window.Event || window.InputEvent;

  var ev = new KeyboardEvent('keydown', {altKey:false,
      bubbles: true,
      code: "Enter",
      key: "Enter",
      keyCode: 13,
      type: "keydown",
      which: 13});


  var event = new InputEvent('input', {
    bubbles: true
  });

  var textbox = document.getElementsByTagName('textarea')[0];

  textbox.textContent = "Testing";
  textbox.dispatchEvent(event);
  textbox.dispatchEvent(ev);