Thanks for your help guys! That explanation makes perfect sense.
Sorry about spamming the change list with so many screenshots! I just thought that the chest image wasn't working.
Well, for example, when you open a chest your hand always does a hitting motion. However, while in the interface of a chain and maybe the other types of command blocks, your hand and the block held go invisible. When you leave the interface the held item or your hand reappears and then it does the hitting motion. Compared to the way a chest is interacted with it seems unintended. Here is a screenshot of the chain command block there is also one of the chest in the gallery. !image-2018-07-05-18-45-03-611.png!
Thank you!
Sorry that I made a duplicate, I used the search feature but it didn't show me the other ticket