MF's q didn't consider as an ability, so Kleptomancy didn't activited as Ez's q can.
Yauso's third q has always been a bug started from the beginning. That third didn't activite a lot of on-hit like the red buff and Kleptomancy.
MF's Q isn't treated like an AA like Ezreal's Q. And neither is Yasuo's 3rd Q. Not bugs.
If you are trying to use MF Q to bounce off a minion and hit a champion then that is why it wont give a klepto proc. Klepto is coded as a sheen, and sheen procs on minions. So sadly when you cast MF Q it will proc the buff on the minion resulting in you not getting anything.
Yas Q is the same, make sure the first enemy hit is a champion.
