You can change the entire look and feel, can able to add button / event / can do anything with it. Read documentation here or more example here
HTML:
<div id="editor" placeholder="Type here ... "></div>
CSS:
<link rel="stylesheet" href="path_to/easyeditor.css">
JS:
<script src="path_to/jquery.min.js"></script> <script src="path_to/jquery.easyeditor.js"></script> <script> jQuery(document).ready(function($) { new EasyEditor('#editor'); }); </script>