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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{
    m_orphanage.EraseForBlock(*pblock);
    m_last_tip_update = GetTime();
    {
        LOCK(m_recent_confirmed_transactions_mutex);
        for (const auto& ptx : pblock->vtx) {
            m_recent_confirmed_transactions->insert(ptx->GetHash());
            if (ptx->GetHash() != ptx->GetWitnessHash()) {
                m_recent_confirmed_transactions->insert(ptx->GetWitnessHash());
            }
        }
    }
    {
        LOCK(cs_main);
        for (const auto& ptx : pblock->vtx) {
            m_txrequest.ForgetTxHash(ptx->GetHash());
            m_txrequest.ForgetTxHash(ptx->GetWitnessHash());
        }
    }
}
void PeerManagerImpl::BlockDisconnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex* pindex)