Literal Gameplay Tag Container's Return Value does not have ParentTags in 4.17 and 4.18. In 4.16, the value had it.
There is same problem in Return node that is Gameplay Tag Container Structure.
In UBlueprintGameplayTagLibrary::MakeLiteralGameplayTagContainer, the value doesn't have ParentTags.
1. Open attached project
2. Play and confirm that output log show "fail"
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-51299 in the post.