[GAMEPLAY] Leona's E doesn't stop abilities.

With various champions Leona's E won't stop them from using an ability. Main issue is with Tristana's rocket jump. I would use my E on them before they use their ability and like once it hits them they jump away. And it registers as me hitting them because a good amount of times during laning phase I would be dragged under turret giving them a free kill. Or it will root trist until I was half way to him (through the E dash) then he would jump and leave me where he stood before. This is a game changing glitch. Also the auto attack after a successful with your Q activated doesn't always stun. Unfortunately I couldn't find any videos on this.