Interesting interaction between Tristana and Katarina I am convinced is a glitch. [GAMEPLAY]

So while playing a ranked game, this happened. I am pretty sure it wasn't the case a while back and so I think this is a bug.

Another gif of this happening in a different situation (Here I think Shunpo happened before Tristana's R even was shot).

And here you can see Shunpo does not go on cd.

To make occur simply have Katarina be shot by Tristana's ult, and have Katarina Shunpo anywhere behind Tristana. So far this has happened every time I tried it in game. But have not been able to test it further because I have no friends.