We have seen a few times oddly incomplete data when authenticating via ipsilon using a fas backend.
This seems to be caused by fas returning some data, then also crashing and returning a 500.
ipsilon goes on from there, but since data is complete sometimes can't login the user, or data like email is missing or return page is odd. In this case it would be good for ipsilon to just error out when it sees the 500 from fas and let the user try again.
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