Trying to inject CSS and JS files reachable through Qt resources (qrc://) through JavaScript (using this technique) which itself is injected through a evalutateJavaScript() call fails fails miserably hitting this test in QNetworkAccessFileBackend. I can't figure how to make this work, really. I could subclass QNAFB but then I would need to subclass QNAM as well to make it instance my subclass instead of QNAFB?