public function getFlashObject($name)
    {
        $serialized = $this->__get($name);

        $object = \is_string($serialized) ? unserialize($serialized, ['allowed_classes' => true]) : $serialized;

        $this->__unset($name);

        if ($name === 'files-upload') {
            $grav = Grav::instance();

            // Make sure that Forms 3.0+ has been installed.
            if (null === $object && isset($grav['forms'])) {
                user_error(
                    __CLASS__ . '::' . __FUNCTION__ . '(\'files-upload\') is deprecated since Grav 1.6, use $form->getFlash()->getLegacyFiles() instead',
                    E_USER_DEPRECATED
                );

                /** @var Uri $uri */
                $uri = $grav['uri'];
                /** @var Grav\Plugin\Form\Forms $form */
                $form = $grav['forms']->getActiveForm();

                $sessionField = base64_encode($uri->url);

                /** @var FormFlash $flash */
                $flash = $form ? $form->getFlash() : null;
                $object = $flash ? [$sessionField => $flash->getLegacyFiles()] : null;
            }
        }

        return $object;
    }