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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int ActiveHeight() const { return ActiveChain().Height(); }
    CBlockIndex* ActiveTip() const { return ActiveChain().Tip(); }
    BlockMap& BlockIndex() EXCLUSIVE_LOCKS_REQUIRED(::cs_main)
    {
        return m_blockman.m_block_index;
    }
    
    
    bool IsSnapshotActive() const;
    std::optional<uint256> SnapshotBlockhash() const;
    
    bool IsSnapshotValidated() const { return m_snapshot_validated; }
    
    
    bool IsBackgroundIBD(CChainState* chainstate) const;
    
    
    
    
    CChainState& ValidatedChainstate() const;
    CChain& ValidatedChain() const { return ValidatedChainstate().m_chain; }
    CBlockIndex* ValidatedTip() const { return ValidatedChain().Tip(); }
    /**
     * Process an incoming block. This only returns after the best known valid
     * block is made active. Note that it does not, however, guarantee that the
     * specific block passed to it has been checked for validity!
     *