Usually, in versions before 1.13, in mac you could open up your inventory and move your cursor around in your inventory instantly, while i've noticed so far as i've played that in this, you have to wait 1-2 seconds before you can move your cursor around after opening up your inventory. It's quite annoying and would be especially annoying if you were competing against other players on a server that required you do things fast. Also, the scroll wheel doesn't work quite right. It doesn't allowed you to move 1 or 2 squares normally, and that's also annoying. I can use the numbers (1-7) just fine, but reaching all the way to 9 is not my thing, and I'd rather use the scroll wheel for that. Very annoying and needs to be fixed for mac players aswell.