Self Cast Priority Bug

Noticed this when playing Orianna and Karma. When your mouse is hovered over a legal target of a shield spell (like Karma/Orianna E) and you try to do a self-cast, the spell will always prioritize the target hovered over by your mouse cursor. Not sure if this also applies to other kinds of spells when self-casted but i imagine it has the same issue. 100% repeatable (at least on these champions), tested multiple times.