newCredential.response?.getAuthenticatorData is not a function

[ForNeVeR]

I'm trying to use KeePassXC's passkey support with WebAuthn.Net, and it fails.

My environment is Windows 11.

1. Install the latest snapshot version KeePassXC (only that one supports passkeys for now).
2. Start KeePassXC, open or create a database.
3. In the KeePassXC settings, enable the browser support, also install the Chrome extension.
4. In the browser extension settings, enable Passkey generator:
   
5. Try to register at https://webauthn.vanbukin.com

Expected result: same as with other passkey providers, it should generate a new passkey and authenticate.
Actual result: KeePassXC successfully shows its window to generate the passkey, but nothing happens after I generate it. The KeePassXC window just closes.

In the browser console, I see the following error message:

Uncaught (in promise) TypeError: newCredential.response?.getAuthenticatorData is not a function
    at completeRegistration (lib.js:129:71)
    at HTMLButtonElement.onRegisterButtonHandler (register.js:100:42)

Note that KeePassXC works well on the test site https://webauthn.io/, so I believe it is a problem with WebAuthn.Net.

[Keroosha]

newCredential.response?.getAuthenticatorData

Was invalid undefined/null check at demo lib.js, fixed at #5682d8a and now should work fine