Karthus Q should have a quick cast indicator if the option is checked

Karthus Q functions the same way with or without quick cast with indicator. This doesn’t make sense. If people use this option they want to see where their shots will go and especially on a champion like karthus it’s crucial because of the way his q actually works ie more damage if it only hits one target. An ability like this should have a quick cast with indicator compatibility. There is no reason for it not to