protected function getCheckoutInjectionVariables() {
        $opts = $this->module->getActingOpts();
        return [
            'amzjsurl' => $opts['amzjsurl'],
            'sandbox' => $opts['sandbox'],
            'merchantId' => $opts['merchant_id'],
            'ledgerCurrency' => $opts['ledgerCurrency'],
            'checkoutLanguage' => $opts['checkoutLanguage'],
            'publicKeyId' => $opts['public_key_id'],
        ];
    }