I receive this error when trying to open `bitcoin-qt` when compiling from `master`:

> terminate called after throwing an instance of 'std::runtime_error'
>   what():  JSON value is not a string as expected
> Aborted

No debug info is generated since the application isn't started.

I am running Qubes 4.0 fully updated, in a Debian-11 VM with normal networking. Intel x86_64
{
#ifdef ENABLE_EXTERNAL_SIGNER
    namespace bp = boost::process;
    UniValue result_json;
    bp::opstream stdin_stream;
    bp::ipstream stdout_stream;
    bp::ipstream stderr_stream;
    if (str_command.empty()) return UniValue::VNULL;
    bp::child c(
        str_command,
        bp::std_out > stdout_stream,
        bp::std_err > stderr_stream,
        bp::std_in < stdin_stream
    );
    if (!str_std_in.empty()) {
        stdin_stream << str_std_in << std::endl;
    }
    stdin_stream.pipe().close();
    std::string result;
    std::string error;
    std::getline(stdout_stream, result);
    std::getline(stderr_stream, error);
    c.wait();
    const int n_error = c.exit_code();
    if (n_error) throw std::runtime_error(strprintf("RunCommandParseJSON error: process(%s) returned %d: %s\n", str_command, n_error, error));
    if (!result_json.read(result)) throw std::runtime_error("Unable to parse JSON: " + result);
    return result_json;
#else