Recreating Kubz NFT Hack and understanding what went wrong

Another day, another white-hat takeover of an NFT project that isn’t writing their proxy contracts correctly. Here is the transaction: https://etherscan.io/tx/0xd9c6c47c20d86a0862d971652a2bc65f7fcb30139fe78ff59a8e3f1c0f634c6a How it happened you may ...