the command "bitcoin-cli getblockstats 0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba" does not work.

It displays "error: Error parsing JSON:0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba"

but it should display the block stats like the documentation says.

also bitcoin-cli getblockstats 0 does not work. block number must be at least 1 to work. But blocks start at 0.

tested with 0.20.1 on freebsd, another user on IRC acknowledged the problem.
cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&height]() EXCLUSIVE_LOCKS_REQUIRED(cs_blockchange) {return latestblock.height >= height || !IsRPCRunning();});
        else
            cond_blockchange.wait(lock, [&height]() EXCLUSIVE_LOCKS_REQUIRED(cs_blockchange) {return latestblock.height >= height || !IsRPCRunning(); });
        block = latestblock;
    }
    UniValue ret(UniValue::VOBJ);
    ret.pushKV("hash", block.hash.GetHex());
    ret.pushKV("height", block.height);
    return ret;
},
    };
}
static RPCHelpMan syncwithvalidationinterfacequeue()
{
    return RPCHelpMan{"syncwithvalidationinterfacequeue",
                "\nWaits for the validation interface queue to catch up on everything that was there when we entered this function.\n",
                {},
                RPCResult{RPCResult::Type::NONE, "", ""},
                RPCExamples{
                    HelpExampleCli("syncwithvalidationinterfacequeue","")
            + HelpExampleRpc("syncwithvalidationinterfacequeue","")
                },
        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
    SyncWithValidationInterfaceQueue();
    return UniValue::VNULL;
},
    };
}
static RPCHelpMan getdifficulty()