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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if (!client->load()) {
            return false;
        }
    }
     *
     i
     a
    if (fPruneMode) {
        LogPrintf("Unsetting NODE_NETWORK on prune mode\n");
        nLocalServices = ServiceFlags(nLocalServices & ~NODE_NETWORK);
        if (!fReindex) {
            LOCK(cs_main);
            for (CChainState* chainstate : chainman.GetAll()) {
                uiInterface.InitMessage(_("Pruning blockstore…").translated);
                chainstate->PruneAndFlush();
            }
        }
    }
    if (chainparams.GetConsensus().SegwitHeight != std::numeric_limits<int>::max()) {
         Adv
         The 
        nLocalServices = ServiceFlags(nLocalServices | NODE_WITNESS);
    }
     ***
    if (!CheckDiskSpace(gArgs.GetDataDirNet())) {
        InitError(strprintf(_("Error: Disk space is low for %s"), gArgs.GetDataDirNet()));
        return false;
    }
    if (!CheckDiskSpace(gArgs.GetBlocksDirPath())) {
        InitError(strprintf(_("Error: Disk space is low for %s"), gArgs.GetBlocksDirPath()));