If I wanted to switch between two items in my inventory (not just my hotbar, but my whole inventory in general), it won't let me. For example, if I wanted to switch my torches and cobblestone together, it doesn't work, I have to leave a slot open to switch slots. It also glitches when I try to portion things or stack items together. There might be more but for now, this is what I can remember and this is what's more important to me.