getMediaThumbnailSizesRo example

'media_folder_configuration.loaded' => [
                ['unserialize', 10],
            ],
        ];
    }

    public function unserialize(EntityLoadedEvent $event): void
    {
        /** @var MediaFolderConfigurationEntity $media */
        foreach ($event->getEntities() as $media) {
            if ($media->getMediaThumbnailSizes() === null) {
                if ($media->getMediaThumbnailSizesRo()) {
                    $media->setMediaThumbnailSizes(unserialize($media->getMediaThumbnailSizesRo()));
                } else {
                    $media->setMediaThumbnailSizes(new MediaThumbnailSizeCollection());
                }
            }
        }
    }
}