What you are complaining about is the game trying to center the unit on screen to the map edges based on where it is in relation to the four borders of the map and what zoom in/out level you are set to
Those buttons have NOTHING to do with what you are seeing. It's been a normal game function for decades
Why anyone would use those keys to zoom in or out the map when it's simpler to just use the number pad - or +on the keyboard is beyond me but they have nothing to do with what you see the game do when you Z fire or X smoke when a unit has smoke