This is related to #14150 and possibly others, but it's actually a separate issue.

For instance, when using the following query:
`bitcoin-cli scantxoutset start '[{"desc":"wpkh(xpubABCDEF/0/*)", "range":100}]'`
I can get a list of UTXOs, but no way to get back the index which derived that particular UTXO. So it's not much better than deriving on the user side and specifying addresses one by one, so that I already have a cache of addresses to match.

Not sure what the solution looks like. One way is to repeat the full descriptor in the utxo. That might get verbose though.
{
        WAIT_LOCK(cs_blockchange, lock);
        block = latestblock;
        if(timeout)
            cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&block]{return latestblock.height != block.height || latestblock.hash != block.hash || !IsRPCRunning(); });
        else
            cond_blockchange.wait(lock, [&block]{return latestblock.height != block.height || latestblock.hash != block.hash || !IsRPCRunning(); });
        block = latestblock;
    }
    UniValue ret(UniValue::VOBJ);
    ret.pushKV("hash", block.hash.GetHex());
    ret.pushKV("height", block.height);
    return ret;
}
static UniValue waitforblock(const JSONRPCRequest& request)
{
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 2)
        throw std::runtime_error(
            "waitforblock <blockhash> (timeout)\n"
            "\nWaits for a specific new block and returns useful info about it.\n"
            "\nReturns the current block on timeout or exit.\n"
            "\nArguments:\n"
            "1. \"blockhash\" (required, string) Block hash to wait for.\n"
            "2. timeout       (int, optional, default=0) Time in milliseconds to wait for a response. 0 indicates no timeout.\n"
            "\nResult:\n"
            "{                           (json object)\n"
            "  \"hash\" : {       (string) The blockhash\n"
            "  \"height\" : {     (int) Block height\n"
            "}\n"
            "\nExamples:\n"