I'm a very organized person and every time before I go into a cave and just anywhere far. I always organize which items I want in the bottom slots bar. But I have noticed that whenever I go into a chest to either grab or put an item inside, the moment I exit the chest I notice that the items in the bottom bar have completely been messed up. Sometimes I have duplicated items, other times those items are exchanged for other items I have in my inventory which I don't want to have in the lower bar while playing the game and it is just frustrating to have to go back and reorganize everything. But it isn't just when I go into chests, its whenever I go into the furnace too, and everything that temporarily removes the bar like going into a chest, furnace, enchanting table, etc.