JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script src="https://rawgit.com/mervick/emojionearea/master/dist/emojionearea.js"></script>
<link rel="stylesheet" href="https://rawgit.com/mervick/emojionearea/master/dist/emojionearea.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<form id="add-msg-form" onsubmit="alert('submit');return false">
        <div class="panel-footer">
            <div class="input-group" style="display: -webkit-box" id="txtbox">
                <textarea id="txtMessage" placeholder="Vui lòng nhập nội dung tin nhắn" ></textarea>
                <span class="input-group-btn">
                    <button class="btn btn-info" id="btnSend" type="submit">Send</button>
                </span>
           </div>
    </div>
</form>

CSS

* {
  font-family: Arial, Helvetica, san-serif;
}
.emojionearea {
  width: 90%;
}
.emojionearea .emojionearea-editor {
    min-height: 1em;
}
.input-group-btn {
    width: 1%;
    display: block;
}

JavaScript

$(document).ready(function() {
	$("#txtMessage").emojioneArea({
    events: {
      keypress: function (editor, event) {
          console.log('event:keypress', event.which); //work
        if(event.which == 13){
          console.log('event:keypress2', event.which); //work
          $('#add-msg-form').submit(); // work
          //$('#txtMessage').val(''); //not work
          $('#txtMessage').data("emojioneArea").setText(""); // this work
        }
      }
    }
  });
});