Try to reproduce jetty issue 9947

Main.java

import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.nio.file.Paths;
import org.eclipse.jetty.jmx.MBeanContainer;
import org.eclipse.jetty.http.HttpFields;
import org.eclipse.jetty.http.HttpMethod;
import org.eclipse.jetty.http.HttpStatus;
import org.eclipse.jetty.http.HttpVersion;
import org.eclipse.jetty.http.MetaData;
import org.eclipse.jetty.http3.api.Session;
import org.eclipse.jetty.http3.api.Stream;
import org.eclipse.jetty.http3.frames.DataFrame;
import org.eclipse.jetty.http3.frames.HeadersFrame;
import org.eclipse.jetty.http3.server.HTTP3ServerConnector;
import org.eclipse.jetty.http3.server.RawHTTP3ServerConnectionFactory;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.util.ssl.SslContextFactory;

public final class Main {

    public static void main(String[] args) throws Exception {
        // Create a Server instance.
        Server server = new Server(9443);

// HTTP/3 is always secure, so it always need a SslContextFactory.
        SslContextFactory.Server sslContextFactory = new SslContextFactory.Server();
        sslContextFactory.setKeyStorePath("/home/strogiyotec/IdeaProjects/archetype/my-artifactId/keystore");
        sslContextFactory.setKeyStorePassword("test322");

// The listener for session events.
        Session.Server.Listener sessionListener = new Session.Server.Listener() {
            @Override
            public Stream.Server.Listener onRequest(Stream.Server stream, HeadersFrame frame) {
                // Send a response after reading the request.
                MetaData.Request request = (MetaData.Request) frame.getMetaData();
                if (frame.isLast()) {
                    respond(stream, request);
                    return null;
                } else {
                    // Demand to be called back when data is available.
                    stream.demand();
                    return new Stream.Server.Listener() {
                        @Override
                        public void onDataAvailable(Stream.Server stream) {
                            Stream.Data data = stream.readData();
                            if (data == null) {
                                stream.demand();
                            } else {
                                // Consume the request content.
                                data.release();

                                if (data.isLast())
                                    respond(stream, request);
                                else
                                    stream.demand();
                            }
                        }
                    };
                }
            }

            private void respond(Stream.Server stream, MetaData.Request request) {
                // Prepare the response HEADERS frame.

                // The response HTTP status and HTTP headers.
                MetaData.Response response = new MetaData.Response(HttpStatus.OK_200, "Test", HttpVersion.HTTP_3, HttpFields.EMPTY);

                if (HttpMethod.GET.is(request.getMethod())) {
                    // The response content.
                    ByteBuffer resourceBytes = ByteBuffer.wrap("Hello world".getBytes(StandardCharsets.UTF_8));

                    // Send the HEADERS frame with the response status and headers,
                    // and a DATA frame with the response content bytes.
                    stream.respond(new HeadersFrame(response, false))
                        .thenCompose(s -> s.data(new DataFrame(resourceBytes, true)));
                } else {
                    // Send just the HEADERS frame with the response status and headers.
                    stream.respond(new HeadersFrame(response, true));
                }
            }
        };
// Create and configure the RawHTTP3ServerConnectionFactory.
        RawHTTP3ServerConnectionFactory http3 = new RawHTTP3ServerConnectionFactory(sessionListener);
        http3.getHTTP3Configuration().setStreamIdleTimeout(15000);

// Create and configure the HTTP3ServerConnector.
        HTTP3ServerConnector connector = new HTTP3ServerConnector(server, sslContextFactory, http3);
// Configure the max number of requests per QUIC connection.
        connector.getQuicConfiguration().setMaxBidirectionalRemoteStreams(1024);
        connector.getQuicConfiguration().setPemWorkDirectory(Paths.get("/home/strogiyotec/IdeaProjects/archetype/my-artifactId"));

// Add the Connector to the Server.
        server.addConnector(connector);
         MBeanContainer mbeanContainer = new MBeanContainer(ManagementFactory.getPlatformMBeanServer());
        server.addBean(mbeanContainer);

// Start the Server so it starts accepting connections from clients.
        server.start();
    }

}