A user reported to me that they are unable to create a PSBT with a legacy watchonly wallet when they use the GUI. They get an error "The amount exceeds your balance".

I think the issue is that the GUI will retrieve the wallet's balance via `AvailableCoins` before calling `CreateTransaction`. This call to `AvailableCoins` is resulting in fewer coins being returned with recent changes to how `AvailableCoins` works, particularly with additional filtering of spendable coins and preset coins.

***

Note that this does not effect descriptor wallets. A workaround for this issue is to switch to using descriptor wallets. An existing legacy wallet can be turned into a descriptor wallet using the `migratewallet` RPC. However many watchonly legacy wallets are likely the result of importing descriptors via `importmulti`. For such wallets, I recommend creating a new descriptor wallet and re-importing the descriptors.
broadcast = complete && !send_failure;
            if (!send_failure) {
                // 
                // 
                if (complete) {
                    // 
                    const CTransactionRef tx = MakeTransactionRef(mtx);
                    m_current_transaction->setWtx(tx);
                } else {
                    presentPSBT(psbtx);
                }
            }
        }
        // 
        // 
        if (broadcast) {
            // 
            model->sendCoins(*m_current_transaction);
            Q_EMIT coinsSent(m_current_transaction->getWtx()->GetHash());
        }
    }
    if (!send_failure) {
        accept();
        m_coin_control->UnSelectAll();
        coinControlUpdateLabels();
    }
    fNewRecipientAllowed = true;
    m_current_transaction.reset();
}
void SendCoinsDialog::clear()