https://github.com/code-423n4/2022-10-zksync/blob/456078b53a6d09636b84522ac8f3e8049e4e3af5/ethereum/contracts/zksync/facets/Mailbox.sol#L222 Maybe it's best to check the length is nonzero before create array.
https://github.com/code-423n4/2022-10-zksync/blob/456078b53a6d09636b84522ac8f3e8049e4e3af5/ethereum/contracts/zksync/facets/Mailbox.sol#L222 Maybe it's best to check the length is nonzero before create array.