When I am breaking any block that has a hardness value using any tool(other than hand)and switch to hand, the game crashes with a null-pointer exception.
That happened to me while I was testing MC-7625, therefore related to MC-7625.
Edit: possibly related to MC-7772.
MC-7625 Can't break blocks with nothing in hand
MC-7622 Snapshot Crash when trying to break sugar cane