Maybe it's totally fine, but it strikes me as one of those weird things that could like cause weird data corruption or something.
All my UI button prefabs have an FSM on their button game object that detects pointer hovers. It's done, so having a template I could just add to all the button prefabs, would be great. But is it safe to have a template on an fsm on a game object inside a prefab? I'm using Unity 2019.2.0f1. and playmaker 1.9.