Browser halts when trying to close browser windows or tab

When I want to close the browser window or tab on a QtQuick application, the browser windows halts. This happens both on Firefox and Chrome.

Firefox detects the non-responding state and offers to stop it or wait but Chrome does not.

adding this to main, seems to solve the problem but I'm still not sure.

QObject::connect(&engine, &QQmlApplicationEngine::quit, &QGuiApplication::quit);