Loading...

XML

Word

Printable

Type: Bug
Resolution: Fixed
Priority: P2: Important
Fix Version/s: 6.7.0 FF
Affects Version/s: 5.15.12, 6.2.7, 6.4.2, 6.5.0 Beta2
Component/s: WebEngine
Labels:
- Reported_by_support_standard
Environment:
Windows 10 22H2 Pro, MSVC 2019 x64

Platform/s:

Linux/X11, Windows
Commits:
889567af4 (112-based), 37430020d (dev)

Code

sample.html

<html><body>
    <img src="https://www.qt.io/hubfs/2016_Qt_Logo/qt_logo_green_rgb_16x16.png" />
</body></html>

main.cpp

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);

    QUrl sampleUrl("qrc:/sample.html");

    QWebEnginePage page;
    page.settings()->setAttribute(QWebEngineSettings::LocalContentCanAccessRemoteUrls, true);

    QObject::connect(&page, &QWebEnginePage::loadProgress, [](int progress)
    {
        qDebug() << "Loading progress:" << progress;
    });
    QObject::connect(&page, &QWebEnginePage::loadFinished, [&]
    {
        qDebug("Finished!");

        static bool firstReload = true;
        if (!firstReload)
        {
            qDebug("Quitting");
            qApp->quit();
            return;
        }

        qDebug("Clearing cache");
        page.profile()->clearHttpCache();

        firstReload = false;

        // WORKAROUND: Wrap the lines below around a QTimer::singleShot()
        //             with a sufficiently large delay (say, 100ms - 500ms)
        qDebug("Reloading...");
        page.load(sampleUrl);
    });
    page.load(sampleUrl);

    return app.exec();
}

Expected output

Loading progress: 0
Loading progress: 70
Loading progress: 80
Loading progress: 100
Finished!
Clearing cache
Reloading...
Loading progress: 0
Loading progress: 70
Loading progress: 100
Finished!
Quitting

Actual output

Loading progress: 0
Loading progress: 70
Loading progress: 80
Loading progress: 100
Finished!
Clearing cache
Reloading...
Loading progress: 0
Loading progress: 80

The 2nd load never finishes so the app never quits.

Notes

This seems to be some kind of race condition:
- On one Windows 10 PC, I can reproduce this 100% of the time on Qt 6.x, but never on Qt 5.15
- On another Windows 10 PC, I can only reproduce this ~50% of the time on all versions of Qt