Azure AD B2C Serialize StringCollection claim in the cookie

问题

I have the following setup for my B2C custom policy:

<TechnicalProfile Id="SM-AAD">
      <DisplayName>Session Mananagement Provider</DisplayName>
      <Protocol Name="Proprietary" Handler="Web.TPEngine.SSO.DefaultSSOSessionProvider, Web.TPEngine, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
      <PersistedClaims>
        <PersistedClaim ClaimTypeReferenceId="objectId" />
        <PersistedClaim ClaimTypeReferenceId="signInName" />
        <PersistedClaim ClaimTypeReferenceId="email" />
        <PersistedClaim ClaimTypeReferenceId="groups" />
        <PersistedClaim ClaimTypeReferenceId="executed-SelfAsserted-Input" />
      </PersistedClaims>
      <OutputClaims>
        <OutputClaim ClaimTypeReferenceId="objectIdFromSession" DefaultValue="true"/>
      </OutputClaims>
    </TechnicalProfile>

Notice one of the persisted claim is of StringCollection <PersistedClaim ClaimTypeReferenceId="groups" /> type. The original values are like:

"groups": ["guid1", "guid2", "guid3", ...]

All the claims are persisted fine in the session (cookie) except the groups claim. Instead of properly serializing/deserializing the values, on the next token request, we've gotten the following in the JWT instead:

"groups": ["System.Collections.Generic.List`1[System.String]"],

Is there a way to properly serialize StringCollection claim type?

来源：https://stackoverflow.com/questions/54981693/azure-ad-b2c-serialize-stringcollection-claim-in-the-cookie