Hey -
Could you provide more details about the behavior you’re seeing in 4.12? There was an issue where custom categories were not properly hidden with the HideCategories specifier, however the bug was fixed for 4.12 (Unreal Engine Issues and Bug Tracker (UE-19743) ).
For example, when I add a new class with the following:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = ActorTick)
float rando;
My float value is correctly hidden in 4.12.