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If I understand correctly,
the first transaction in a block may collect transaction fees (difference between inputs and outputs) from the following transactions in the same block; and
subsequent transactions may use outputs from previous transactions in the same block.
If the block maturity check is disabled, so that newly minted coins may be utilized immediately, can a circular dependency of transactions arise, i.e., a miner uses coins generated from the coinbase to pay for transaction fee of a transaction in the same block, but the fee is then returned back to themselves (collected by the coinbase)?