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When deploying custom authentication flows, you may need to teach the IdP how to store the results your flows create. The system comes with support built-in for storing results produced by LDAP and some of the other custom Principal types used by the IdP for its own use, and as of V3.3 it's possible to extend this set. If you need to preserve custom Principal types the IdP doesn't know about, you will need to create a plugin that implements the PrincipalSerializer interface, and register it with the system by defining a new bean in conf/authn/general-authn.xml that merges your custom plugin definition into the list of default serializers:
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