it happened as i had prefab buildings which contains prefabs inside.
i explain with a screenshot and notes in it.
so if me apply a prefab normal the other prefabs get an update,
here at least the fsm icon should appear.
but if a prefab is inside other prefab not
the prefab cube i put for testing in a cylinder prefab.
me using 1.7.8.4
edit:
it seems this is a bug from unity first.
also i saw someone else asked when its solved.
for myself its an important issue.
