Union types #4838
Instead throw the generic invalid type message. Otherwise we may run into issues if a union type contains an invalid type, but also a valid one.
The uttermost shame is that I am long since subscribed to the internals list, but I couldn't get myself to wade through the nonsense of the attached .eml forest that is a PITA to view :/
Perhaps it is just time to switch to the regular format from the digest stuff.