you probably crafted a debug stick with a placeholder block and a stick in bedrock's very first edition, then left clicked to get spam debug sticks, then tinkered with the games code, so that if you change a texture with a debug stick, if there are any more, they all activate, and then you had to save first to get back in the game with the very same inventory, and then you clicked your debug stick and then all of them activated and then the game crashed. if you used a placeholder block (WITHOUT CRAFTING A DEBUG STICK) and did the same things (the scenarios are probably similar), you got a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block layered over a placeholder block and blablablablablablablablabla
that would be the similar scenario and therefore why the game has frozen.
