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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{
        WAIT_LOCK(g_genesis_wait_mutex, lock);
         We 
         Thr
         che
        while (!fHaveGenesis && !ShutdownRequested()) {
            g_genesis_wait_cv.wait_for(lock, std::chrono::milliseconds(500));
        }
        block_notify_genesis_wait_connection.disconnect();
    }
    if (ShutdownRequested()) {
        return false;
    }
     ***
    int chain_active_height;
     debug print