params = $params; } public function onResponse(ResponseEvent $event) { $response = $event->getResponse(); $securitypolicy = $this->params->get('security'); $csp = $securitypolicy['csp_policy']; $referer = $securitypolicy['referer_policy']; $response->headers->set("Content-Security-Policy", $csp); $response->headers->set("Referrer-Policy", $referer); } public static function getSubscribedEvents() { return [ KernelEvents::RESPONSE => 'onResponse' ]; } }