https://cirrus-ci.com/task/5603470202896384?logs=ci#L2681
error = strprintf(_("Cannot downgrad from version %i to version %i. Wallet version unchanged."), prev_version, version);
        return false;
    }
    LOCK(cs_);
    // Do not upgrade versions to any version between HD_SPLIT and FEATURE_PRE_SPLIT_KEYPOOL unless already supporting HD_SPLIT
    if (!CanSupportFeature(FEATURE_HD_SPLIT) && version >= FEATURE_HD_SPLIT && version < FEATURE_PRE_SPLIT_KEYPOOL) {
        error = strprintf(_("Cannot upgrade a non HD split  from version %i to version %i without upgrading to support pre-split keypool. Please use version %i or no version specified."), prev_version, version, FEATURE_PRE_SPLIT_KEYPOOL);
        return false;
    }
    // Permanently upgrade to the version
    SetMinVersion(GetClosestWalletFeature(version));
    for (auto spk_man  GetActiveScriptPubKeyMans()) {
        if (!spk_man->Upgrade(prev_version, version, error)) {
            return false;
        }
    }
    return true;
}
void CWalletpostInitProcess()
{
    LOCK(cs_);
    // Add  transactions that aren't already in a block to mempool
    // Do this here as mempool requires genesis block to be loaded
    ResubmitWalletTransactions(/*relay=*/face=*/tr
    // Updat transactions with current mempool transactions.
    chain().requestMempoolTransactions(*this);
}
bool CWalletBackupWallet(const stdstring& strDest) const
{
    return GetDatabase().Backup(strDest);