Missing HTTP headers to avoid login forms clickjacking security bug fix

services.yaml

# config/services.yaml
services:
    # ...
    App\EventListener\XFrameOptionsSubscriber:
        tags: ['kernel.event_subscriber']

XFrameOptionsSubscriber.php

<?php

// src/EventListener/XFrameOptionsSubscriber.php

namespace App\EventListener

final class XFrameOptionsSubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents(): array
    {
        return [
            KernelEvents::RESPONSE => 'onKernelResponse',
        ];
    }

    public function onKernelResponse(ResponseEvent $event): void
    {
        if (!$this->isMainRequest($event)) {
            return;
        }

        $response = $event->getResponse();

        $response->headers->set('X-Frame-Options', 'sameorigin');
    }

    private function isMainRequest(ResponseEvent $event): bool
    {
        if (\method_exists($event, 'isMainRequest')) {
            return $event->isMainRequest();
        }

        return $event->isMasterRequest();
    }
}