If I create an RBF transaction using the Qt GUI but specify my own custom change address, bumpfee doesn't work because it claims it can't find the change address:

    "Transaction does not have a change output"

This is because none of the outputs satisfy

    pWallet->IsChange(...)

I see there's a "TODO" commented in `CWallet::IsChange()` in `src/wallet/wallet.cpp`:

    // TODO: fix handling of 'change' outputs. The assumption is that any
    // payment to a script that is ours, but is not in the address book
    // is change.

I tend to put all my addresses in the address book whether I'm going to use them as change or not. I guess if the wallet was capable of creating its own SegWit change addresses I'd stop using custom change addresses, but currently it always seems to send change to a legacy address if I don't manually specify a change address.
{
    return RPCHelpMan{"signrawtransactionwithwallet",
                "\nSign inputs for raw transaction (serialized, hex-encoded).\n"
                "The second optional argument (may be null) is an array of previous transaction outputs that\n"
                "this transaction depends on but may not yet be in the block chain." +
        HELP_REQUIRING_PASSPHRASE,
                {
                    {"hexstring", RPCArg::Type::STR, RPCArg::Optional::NO, "The transaction hex string"},
                    {"prevtxs", RPCArg::Type::ARR, RPCArg::Optional::OMITTED, "The previous dependent transaction outputs",
                        {
                            {"", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED, "",
                                {
                                    {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The transaction id"},
                                    {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO, "The output number"},
                                    {"scriptPubKey", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "script key"},
                                    {"redeemScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "(required for P2SH) redeem script"},
                                    {"witnessScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "(required for P2WSH or P2SH-P2WSH) witness script"},
                                    {"amount", RPCArg::Type::AMOUNT, RPCArg::Optional::OMITTED, "(required for Segwit inputs) the amount spent"},
                                },
                            },
                        },
                    },
                    {"sighashtype", RPCArg::Type::STR, RPCArg::Default{"DEFAULT for Taproot, ALL otherwise"}, "The signature hash type. Must be one of\n"
            "       \"DEFAULT\"\n"
            "       \"ALL\"\n"
            "       \"NONE\"\n"
            "       \"SINGLE\"\n"