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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return InitError(strprintf(_("Invalid -proxy address or hostname: '%s'"), proxyArg));
        SetProxy(NET_IPV4, addrProxy);
        SetProxy(NET_IPV6, addrProxy);
        SetProxy(NET_ONION, addrProxy);
        SetNameProxy(addrProxy);
        SetReachable(NET_ONION, true); 
    }
    
    
    
    std::string onionArg = args.GetArg("-onion", "");
    if (onionArg != "") {
        if (onionArg == "0") { 
            SetReachable(NET_ONION, false);
        } else {
            CService onionProxy;
            if (!Lookup(onionArg, onionProxy, 9050, fNameLookup)) {
                return InitError(strprintf(_("Invalid -onion address or hostname: '%s'"), onionArg));
            }
            proxyType addrOnion = proxyType(onionProxy, proxyRandomize);
            if (!addrOnion.IsValid())
                return InitError(strprintf(_("Invalid -onion address or hostname: '%s'"), onionArg));
            SetProxy(NET_ONION, addrOnion);
            SetReachable(NET_ONION, true);
        }
    }
    for (const std::string& strAddr : args.GetArgs("-externalip")) {
        CService addrLocal;
        if (Lookup(strAddr, addrLocal, GetListenPort(), fNameLookup) && addrLocal.IsValid())
            AddLocal(addrLocal, LOCAL_MANUAL);