| Index: composer.html | 
| =================================================================== | 
| --- a/composer.html | 
| +++ b/composer.html | 
| @@ -19,16 +19,17 @@ | 
|  | 
| <html> | 
| <head> | 
| <meta charset="utf-8"> | 
| <title>Block element</title> | 
| <link type="text/css" href="jquery-ui/css/smoothness/jquery-ui-1.12.1.custom.css" rel="stylesheet" /> | 
| <script type="text/javascript" src="jquery-ui/js/jquery-3.2.1.min.js"></script> | 
| <script type="text/javascript" src="jquery-ui/js/jquery-ui-1.12.1.custom.min.js"></script> | 
| +<script type="text/javascript" src="polyfill.js"></script> | 
| <script type="text/javascript" src="ext/common.js"></script> | 
| <script type="text/javascript" src="ext/content.js"></script> | 
| <script type="text/javascript" src="i18n.js" charset="utf-8"></script> | 
| <script type="text/javascript" src="composer.js" charset="utf-8"></script> | 
| <style type="text/css"> | 
| * | 
| { | 
| box-sizing: border-box; | 
|  |