Hi Steve,
The test case for HHH-12087 shows that executing a query that has a
transient entity bound to it will cause that transient entity to be
persisted.
Please take a look at the PR for HHH-12087:
https://github.com/hibernate/hibernate-orm/pull/2054
It removes IncrediblySillyJpaMapsIdMappedIdentifierValueMarshaller#persistTransientEntity
and, AFAICT, doesn't break anything.
Thanks,
Gail