[BUG] Miss Fortune's ultimate not showing that it's on CD

I'm not actually sure if the problem is that it's on cd and not showing up or not, and I'm not even sure how to replicate it, but I've had this happen to me twice before.

My best guess for recreation, is that if you try to use her ult right before dying, it goes on cd, but it appears to be off cd. So you can't actually use it again until the cd is off, but there's no way to tell whether it's up or not.