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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{
    std::set<uint256> unbroadcast_txids = m_mempool.GetUnbroadcastTxs();
    for (const auto& txid : unbroadcast_txids) {
        CTransactionRef tx = m_mempool.get(txid);
        if (tx != nullptr) {
            LOCK(cs_main);
            _RelayTransaction(txid, tx->GetWitnessHash());
        } else {
            m_mempool.RemoveUnbroadcastTx(txid, true);
        }
    }
    
    
    const std::chrono::milliseconds delta = std::chrono::minutes{10} + GetRandMillis(std::chrono::minutes{5});
    scheduler.scheduleFromNow([&] { ReattemptInitialBroadcast(scheduler); }, delta);
}
void PeerManagerImpl::FinalizeNode(const CNode& node)