I just tried updating the theme on a live client site and everything went smoothly until I looked at the site on the front end. Everything seemed to be out of whack in terms of layout from what it was prior, so I went into the customize portion and got this error
Fatal error: Call to undefined method Cornerstone_Common::get_app_route_url() in /wp-content/themes/x/framework/functions/admin/customizer.php on line 36
I reverted the theme back and everything went back to normal. Any assistance would be greatly appreciated.