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The registration flow collects the username as a first step so it can look up any registered credentials before passing control to the authentication system. This information can be accessed in the MFA configuration using the isWebAuthnAvailable() method on the WebAuthnRegistrationContext, to decide which flow to use. The example MFA Flow With Password Fallback is a suitable initial setup that allows users to register their first credentials upon inputting their username and password; other combinations are possible.
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Configuration Steps
Other than following step 1, you do not need to change any of the default registration options to register and use a FIDO2 credential with the IdP successfully. If you do want more control over the process, there are a few options available:
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