Nemesis Mod question

I have a Nemesis clone and it came with an extra extension for the tube.I have always wondered what it is for,can anyone help me on this one?

Fatal error: Uncaught Exception: 12: REST API is deprecated for versions v2.1 and higher (12) thrown in /home/ecigfm/public_html/wp-content/plugins/seo-facebook-comments/facebook/base_facebook.php on line 1273