<input type="text" id="input">
<script>
    const testES256PrivateKeyBase64 =
        "BDj/zxSkzKgaBuS3cdWDF558of8AaIpgFpsjF/Qm1749VBJPgqUIwfhWHJ91nb7U" +
        "PH76c0+WFOzZKslPyyFse4goGIW2R7k9VHLPEZl5nfnBgEVFh5zev+/xpHQIvuq6" +
        "RQ==";
    if (window.internals) {
        internals.setMockWebAuthenticationConfiguration({
            local: {
                userVerification: "yes",
                acceptAttestation: false,
                privateKeyBase64: testES256PrivateKeyBase64,
           }
        });
        internals.withUserGesture(() => { input.focus(); });
    }

    const options = {
        publicKey: {
            rp: {
                name: "localhost",
            },
            user: {
                name: "John Appleseed",
                id: new Uint8Array(16),
                displayName: "Appleseed",
            },
            challenge: new Uint8Array(16),
            pubKeyCredParams: [{ type: "public-key", alg: -7 }],
            attestation: "direct",
            timeout: 100,
        }
    };

    navigator.credentials.create(options).then(credential => {
        // console.log("Succeeded!");
        window.webkit.messageHandlers.testHandler.postMessage("Succeeded!");
    }, error => {
        // console.log(error.message);
        window.webkit.messageHandlers.testHandler.postMessage(error.message);
    });
</script>