I have been seeing this lots of times lately.
When opening a product page I get the message
Error: invalid version specified
in a red box and white page.
Well it looks like the Social Buttons Addon is having an issue with Facebook javascript.
so to the file
responsive / templates / addons / social_buttons / providers / facebook.tpl
at line 10 add &version=v2.7 jsut after the &appId={$addons.social_buttons.facebook_app_id}
$.getScript("//connect.facebook.net/{$addons.social_buttons.facebook_lang}/all.js#xfbml=1&appId={$addons.social_buttons.facebook_app_id}&version=v2.7", function () {
Clean your store cache an reload. Should be ok now.
It looks like the template on Like button is incomplete; upon clicking on the "Get Code" button Facebook will generate you a complete template with the version parameter included.
Hope this helps someone with the same trouble I had.
Fotis