There are some potential feefilter cleanups mentioned and motivated in comment https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-805808485 . If you address the locking one, please be careful and make sure that `round()` is only called under a lock. See https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-807992199

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pfrom.cleanSubVer = cleanSubVer;
        }
        peer->m_starting_height = starting_height;
        
        pfrom.fClient = (!(nServices & NODE_NETWORK) && !(nServices & NODE_NETWORK_LIMITED));
        
        pfrom.m_limited_node = (!(nServices & NODE_NETWORK) && (nServices & NODE_NETWORK_LIMITED));
        if (pfrom.m_tx_relay != nullptr) {
            LOCK(pfrom.m_tx_relay->cs_filter);
            pfrom.m_tx_relay->fRelayTxes = fRelay; 
        }
        if((nServices & NODE_WITNESS))
        {
            LOCK(cs_main);
            State(pfrom.GetId())->fHaveWitness = true;
        }
        
        {
        LOCK(cs_main);
        UpdatePreferredDownload(pfrom, State(pfrom.GetId()));
        }
        if (!pfrom.IsInboundConn() && !pfrom.IsBlockOnlyConn()) {