static public function transApiDoc(string $translationPath, array $parameters = [], $locale = null) {
        if (static::class === self::class) {
            // redirect CmfConfig::transApiDoc() calls to primary config class
            return self::getPrimary()->transApiDoc($translationPath, $parameters, $locale);
        } else {
            $translationPath = 'api_docs.' . ltrim($translationPath, '.');
            return static::transCustom($translationPath, $parameters, $locale);
        }
    }