chromium/components/test/data/payments/csp_test_iframe.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=0.5, maximum-scale=0.5, minimum-scale=0.5">
    <meta
      http-equiv="Content-Security-Policy"
      content="default-src 'none'; script-src 'unsafe-eval' 'unsafe-inline'; img-src 'self' https://kylepay.test:*"
    >
    <script>
    async function checkCanMakePayment() {
      const methodData = [{
        supportedMethods: "https://kylepay.test/webpay",
      }];
      let details = {
        total: {
          label: "Total",
          amount: {
            currency: "USD",
            value: "1.00",
          },
        },
      };
      let result = '';
      try {
        const request = new PaymentRequest(methodData, details);
        result = await request.canMakePayment();
      } catch (error) {
        result = error.toString();
      }
      document.querySelector("#output").innerText = "canMakePayment: " + result;
      return result;
    }

    </script>
  </head>
  <body>
    <p>This page is a regression test for <a
      href="https://crbug.com/1055360">crbug/1055360</a> and <a
      href="https://crbug.com/1013080">crbug/1013080</a>.</p>
    <div id="output"></div>
  </body>
</html>