There is a bug or behavior that I consider inappropriate with the flash behavior.
If an object has the flash off and is in the invisible state and you tell it to "stop flashin" the object becomes visible.
That should not happen, the flash behavior should check before being disabled if the object has the behavior enabled:
If you have flash behavior enabled
It is deactivated and the object becomes visible
Maybe it also happens in C3 (I don't use c3) but as they no longer fix bugs that are not a priority in C2 it is useless to report it there.