protected function defuseKey(): string
    {
        try { // Catch Defuse exceptions.
            if (!($key = DefuseKey::createNewRandomKey()->saveToAsciiSafeString())) {
                throw new Exception('Failed to generate an encryption key.');
            }
        } catch (\Throwable $Exception) {
            throw $Exception; // Re-throw.
        }
        return $key;
    }