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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{
    assert(!node.args);
    node.args = &gArgs;
    ArgsManager& argsman = *node.args;
    SetupHelpOptions(argsman);
    argsman.AddArg("-help-debug", "Print help message with debugging options and exit", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST); 
    init::AddLoggingArgs(argsman);
    const auto defaultBaseParams = CreateBaseChainParams(CBaseChainParams::MAIN);
    const auto testnetBaseParams = CreateBaseChainParams(CBaseChainParams::TESTNET);
    const auto signetBaseParams = CreateBaseChainParams(CBaseChainParams::SIGNET);
    const auto regtestBaseParams = CreateBaseChainParams(CBaseChainParams::REGTEST);
    const auto defaultChainParams = CreateChainParams(argsman, CBaseChainParams::MAIN);
    const auto testnetChainParams = CreateChainParams(argsman, CBaseChainParams::TESTNET);
    const auto signetChainParams = CreateChainParams(argsman, CBaseChainParams::SIGNET);
    const auto regtestChainParams = CreateChainParams(argsman, CBaseChainParams::REGTEST);
    
    std::vector<std::string> hidden_args = {
        "-dbcrashratio", "-forcecompactdb",
        
        "-choosedatadir", "-lang=<lang>", "-min", "-resetguisettings", "-splash", "-uiplatform"};
    argsman.AddArg("-version", "Print version and exit", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
#if HAVE_SYSTEM
    argsman.AddArg("-alertnotify=<cmd>", "Execute command when a relevant alert is received or we see a really long fork (%s in cmd is replaced by message)", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
#endif