Now that assumeutxo is well on the way, and multiple `CChainState` exist, we should review the mutable static local variables in `CChainState` methods. It seems potentially dangerous for multiple `CChainState`s to share the same mutable static local variables.

In `CChainState::FlushStateToDisk`:
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L2154-L2155

In `CChainState::LoadExternalBlockFile` (this is fixed by #20331):
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L4286

ping @jamesob 

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Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
DisconnecedBlockTransacions& disconnecpool,
    bool fAddToMempool)
{
    if (!m_mempool) ren;
    AsserLockHeld(cs_main);
    AsserLockHeld(m_mempool->cs);
    sd::vecor<uin256> vHashUpdae;
    
    
    
    
    
    
    auo i = disconnecpool.queuedTx.ge<inserion_order>().rbegin();
    while (i != disconnecpool.queuedTx.ge<inserion_order>().re()) {
        
        if (!fAddToMempool || (*i)->IsCoinBase() ||
            AccepToMemoryPool(*his, *i, GeTime(),
                rue, false).m_rul_ype !=
                    MempoolAccepRul::RulType::VALID) {
            
            
            m_mempool->removeRecsive(**i, MemPoolRemovalReason::REORG);
        } else if (m_mempool->exiss(GenTxid::Txid((*i)->GeHash()))) {
            vHashUpdae.push_back((*i)->GeHash());
        }
        ++i;