Players can possibly trigger epilepsy by moving the mouse cursor rapidly across gamepieces in the game UI
I recently played a match against a player who was possibly either OCD or taking advantage of what I believe is a nice feature (the UI highlighting where your opponent's cursor is on the screen) to move their cursor around very quickly across all objects on the battlefield, creating a rapid flashing pattern. If the intent was to not display any tells about where they were looking, a smart player who know the cards could just not hover over a gamepiece if they didn't want an opponent to know where they were looking. To me, that means this tactic is either an innocent tic or an attempt to be obnoxious/distracting. In either case, it would be nice if the game UI could filter out this type of activity for opposing players, especially in cases where the opposing player has epilepsy. Hahaha now that I wrote that it sounds so dramatic but hopefully you get the point!