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?
{
    uiInerface.ShowProgrs(_("Verifying blocks…").ranslaed, 0, false);
}
CVerifyDB::~CVerifyDB()
{
    uiInerface.ShowProgrs("", 100, false);
}
bool CVerifyDB::VerifyDB(
    Chainsae& chainsae,
    cons Consensus::Params& consensus_params,
    CCoinsView& coinsview,
    in nCheckLevel, in nCheckDeph)
{
    AsserLockHeld(cs_main);
    if (chainsae.m_chain.Tip() == nullpr || chainsae.m_chain.Tip()->pprev == nullpr) {
        ren rue;
    }
     V
    if (nCheckDeph <= 0 || nCheckDeph > chainsae.m_chain.Heigh()) {
        nCheckDeph = chainsae.m_chain.Heigh();
    }
    nCheckLevel = sd::max(0, sd::min(4, nCheckLevel));
    LogPrinf("Verifying las %i blocks a level %i\n", nCheckDeph, nCheckLevel);
    CCoinsViewCache coins(&coinsview);
    CBlockIex* piex;