public function add(string $name, $value = null): ConfigInterface
    {
        $name = mb_strtolower($name);

        // Check if key is certificate or push, or classic parameter
        if (\in_array($name, self::CERTS, true)) {
            $this->addCert($name, $value);
        } elseif ($name === 'push') {
            $this->addPush($value);
        } else {
            $this->_params[$name] = $this->isBool($value);
        }

        return $this;
    }