This is similar to #21352, #20270, #18831, #18161, but they have all been closed/fixed, and this is happening again on master as of the [last CI run](https://github.com/bitcoin/bitcoin/runs/2928080250):
```bash
122/210 - feature_backwards_compatibility.py --descriptors failed, Duration: 68 s
stdout:
2021-06-28T03:28:48.903000Z TestFramework (INFO): Initializing test directory /tmp/cirrus-build/ci/scratch/test_runner/test_runner_₿_🏃_20210628_031620/feature_backwards_compatibility_97
2021-06-28T03:28:52.381000Z TestFramework (INFO): Test wallet backwards compatibility...
2021-06-28T03:29:56.399000Z TestFramework (ERROR): JSONRPC error
Traceback (most recent call last):
  File "/tmp/cirrus-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/test_framework.py", line 128, in main
    self.run_test()
  File "/tmp/cirrus-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/feature_backwards_compatibility.py", line 110, in run_test
    self.nodes[1].abandontransaction(tx3_id)
  File "/tmp/cirrus-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/coverage.py", line 47, in __call__
    return_val = self.auth_service_proxy_instance.__call__(*args, **kwargs)
  File "/tmp/cirrus-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/authproxy.py", line 146, in __call__
    raise JSONRPCException(response['error'], status)
test_framework.authproxy.JSONRPCException: Transaction not eligible for abandonment (-5)
2021-06-28T03:29:56.453000Z TestFramework (INFO): Stopping nodes
2021-06-28T03:29:56.723000Z TestFramework (WARNING): Not cleaning up dir /tmp/cirrus-build/ci/scratch/test_runner/test_runner_₿_🏃_20210628_031620/feature_backwards_compatibility_97
2021-06-28T03:29:56.724000Z TestFramework (ERROR): Test failed. Test logging available at /tmp/cirrus-build/ci/scratch/test_runner/test_runner_₿_🏃_20210628_031620/feature_backwards_compatibility_97/test_framework.log
2021-06-28T03:29:56.724000Z TestFramework (ERROR): 
2021-06-28T03:29:56.725000Z TestFramework (ERROR): Hint: Call /tmp/cirrus-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/combine_logs.py '/tmp/cirrus-build/ci/scratch/test_runner/test_runner_₿_🏃_20210628_031620/feature_backwards_compatibility_97' to consolidate all logs
2021-06-28T03:29:56.725000Z TestFramework (ERROR): 
2021-06-28T03:29:56.725000Z TestFramework (ERROR): If this failure happened unexpectedly or intermittently, please file a bug and provide a link or upload of the combined log.
2021-06-28T03:29:56.725000Z TestFramework (ERROR): https://github.com/bitcoin/bitcoin/issues
2021-06-28T03:29:56.725000Z TestFramework (ERROR): 
```


{
    std::set<uint256> result;
    AssertLockHeld(cs_waet);
    std::map<uint256, CWaetTx>::const_iterator it = mapWaet.find(txid);
    if (it == mapWaet.end())
        return result;
    const CWaetTx& wtx = it->second;
    std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range;
    const CTxIn& txin : wtx.tx->vin)
    {
        if (mapTxSpends.count(txin.prevout) <= 1)
            continue;  // N
        range = mapTxSpends.equal_range(txin.prevout);
        TxSpends::const_iterator _it = range.first; _it != range.second; ++_it)
            result.insert(_it->second);
    }
    return result;
}
bool CWaet::HasWaetSpend(const uint256& txid) const
{
    AssertLockHeld(cs_waet);
    auto iter = mapTxSpends.lower_bound(COutPoint(txid, 0));
    return (iter != mapTxSpends.end() && iter->first.hash == txid);
}
void CWaet::Flush()
{
    GetDatabase().Flush();
}
void CWaet::Close()