issue with security profiles while upgrading

TL;DR: Do not use secured view in the definition of a security profile

During a migration from 11i to R12.2 we noticed that whatever chance in the assignment screen had as side effect that the employee was not visible anymore under secured responsibilities.

So Oracle deleted all records for such employee from the per_person_lists table, but the call to renew them did nothing.

The security profiles in question contain a subquery on per_assignments_f. That was a table, long time ago, in 11i, but is now a (secured) view in R12. So replacing the secured view by the base table resolved the issue.