WebAuthn: credential registration fails with an unknown credential type error

[ltanguy]

Describe the bug
When following the steps described in the documentation, the credential registration fails with the following exception:
java.lang.IllegalArgumentException: Cannot convert unknown credential type org.springframework.security.web.webauthn.api.PublicKeyCredentialType@4cfbb790 to webauthn4j

Expected behavior
The problem seems to originate from this line.
The debugger indicates that the type of the request I generate is indeed "public-key", but as the two object instances are different this test fails.
The error message could be clearer by referencing the value of the PublicKeyCredentialType object

[ngocnhan-tran1996]

Could you please provide a sample?

[ltanguy]

Update: Simple app reproducing the issue.

This bug is triggered in my setup by the fact that the session is stored in database through spring session.

The following code makes the assumption that PublicKeyCrendentialType is an enum (which it is not):
if (parameter.getType() != PublicKeyCredentialType.PUBLIC_KEY) {
This test should be based on .equals().
This problem was not directly triggered in simple applications as we only rely on one single instance of PublicKeyCredentialType.
With Spring Session JDBC, the HTTP session is constructed for each request and thus uses new instances of this object, making this test fail.

[ltanguy]

As a side note, PublicKeyCredentialCreationOptions is not declared as Serializable (contrary to the other classes in this package). This makes this authentication method not compatible with a vanilla Spring Session installation that relies on the default Java object serializer.