getThumbnailsRo example

    public function unserialize(EntityLoadedEvent $event): void
    {
        /** @var MediaEntity $media */
        foreach ($event->getEntities() as $media) {
            if ($media->getMediaTypeRaw()) {
                $media->setMediaType(unserialize($media->getMediaTypeRaw()));
            }

            if ($media->getThumbnails() === null) {
                if ($media->getThumbnailsRo()) {
                    $media->setThumbnails(unserialize($media->getThumbnailsRo()));
                } else {
                    $media->setThumbnails(new MediaThumbnailCollection());
                }
            }
        }
    }

    private function addThumbnailUrl(MediaThumbnailEntity $thumbnail, MediaEntity $media): void
    {
        $thumbnail->setUrl(