[Gameplay] Glitch with Sejuani

In my past 2 games with an opposing summoner using Sejuani I noticed a bug that seemed to be related to either Arctic Assault or Flail of the Northern Winds. Both players had the new Poro skin on which may have something to do with it. Every time she used one of those abilities(Not 100% sure which one) while in the fog of war she would become visible(but not targetable) on the map as well as minimap.