if (spenderAllowance == type(uint256).max) {
	return ;
}

if (spenderAllowance < amount) {
	revert FETH_Insufficient_Allowance(spenderAllowance);
}
// The check above ensures allowance cannot underflow.
unchecked {
	spenderAllowance -= amount;
}
accountInfo.allowance[msg.sender] = spenderAllowance;
emit Approval(from, msg.sender, spenderAllowance);
