private function getLocalizedLabelsFromTypoScript($extensionName)
    {
        if ($extensionName === '') {
            throw new \InvalidArgumentException('The parameter $extensionName must not be empty.', 1331489630);
        }

        $result = [];
        $namespace = 'plugin.tx_' . $extensionName . '._LOCAL_LANG.' . $this->languageKey;

        $configuration = \Tx_Oelib_ConfigurationRegistry::get($namespace);
        foreach ($configuration->getArrayKeys() as $key) {
            $result[$key] = $configuration->getAsString($key);
        }

        return $result;
    }