Credit-Back Address: Address to which all excess gas is credited on L2; i.e., excess ETH for base submission cost (MaxSubmissionCost - ActualSubmissionCostPaid) and excess ETH provided for L2 execution ( (GasPrice x MaxGas) - ActualETHSpentInExecution).
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Submission fee is collected: submission fee is deducted from the senders L2 account; MaxSubmissionCost - submission fee is credited to Credit-Back Address.
     * @notice Put a message in the L2 inbox that can be reexecuted for some fixed amount of time if it reverts
     * @dev all msg.value will deposited to callValueRefundAddress on L2
     * @param destAddr destination L2 contract address
     * @param l2CallValue call value for retryable L2 message
     * @param  maxSubmissionCost Max gas deducted from user's L2 balance to cover base submission fee
     * @param excessFeeRefundAddress maxgas x gasprice - execution cost gets credited here on L2 balance
     * @param callValueRefundAddress l2Callvalue gets credited here on L2 if retryable txn times out or gets cancelled
     * @param maxGas Max gas deducted from user's L2 balance to cover L2 execution
     * @param gasPriceBid price bid for L2 execution
     * @param data ABI encoded data of L2 message
     * @return unique id for retryable transaction (keccak256(requestID, uint(0) )
     */
    function createRetryableTicket(
        address destAddr,
        uint256 l2CallValue,
        uint256 maxSubmissionCost,
        address excessFeeRefundAddress,
        address callValueRefundAddress,
        uint256 maxGas,
        uint256 gasPriceBid,
        bytes calldata data
    ) external payable virtual override onlyWhitelisted returns (uint256) {
    uint256 _ticketID = inbox.createRetryableTicket{ value: msg.value }(
      address(executor),
      0,
      _maxSubmissionCost,
      msg.sender,   // @audit : excessFeeRefundAddress
      msg.sender,  // @audit: callValueRefundAddress
      _gasLimit,
      _gasPriceBid,
      _data
    );
If the Retryable Ticket is cancelled or expires before it is redeemed, Callvalue is credited to Beneficiary.
