QNetworkAccessManager created in the main.cpp and provided to the QQmlApplicationEngine 

QQmlApplicationEngine engine;

engine.setNetworkAccessManagerFactory(new NetworkFactory(m_net));

When QML Image displays image by url from the net, periodically appears errors:

qt.network.http2.connection: [0x1fd586cec10] Connection error: HEADERS on invalid stream (1)
qt.network.http2: stream 11 error: "HEADERS on invalid stream"
qt.network.http2: stream 11 finished with error: "HTTP/2 protocol error"
QML QQuickImage: HTTP/2 protocol error

Error appears on Qt 6.9.1

Everything works fine on Qt 6.6.3

Also works fine on Qt 6.10 beta2