22w44a Block Bug

If you set an item to be a specific block in a specific amount, it will not update the Hotbar when you place a block down until you open a chest or the like.

Or drop an item from that stack.

 

In the image, I had 64 dirt in the last slot, not 59.

 

I used a repeating command block.

Command:

/item replace entity Player hotbar.8 with dirt 64