There seems to be a small error coming up in my developer screen for FB.getLoginStatus() called before calling FB.init().
It seems that adding "status=0" to the all.js call fixes the issue.
I added &status=0 to really-simple-facebook-twitter-share-buttons.php in lines 114 and 305 and the warnings went away.
js.src = "//connect.facebook.net/'.$really_simple_share_option['locale'].'/all.js#xfbml=1&status=0'.$app_id.'";
js.src = "//connect.facebook.net/'.$option['locale'].'/all.js#xfbml=1&status=0'.$app_id.'";