In our software we are experiencing a crash in the accessibility wrapper for the webengine. If a QWebEnginePage loads a website without being added to a QWebEngineView, triggering the accessibility will cause a nullptr dereference of the parent in the BrowserAccessibilityInterface's init.

void BrowserAccessibilityInterface::init()
{
    if (m_id)
        return;

    Q_ASSERT(parent());
    Q_ASSERT(parent()->object());

    m_object = new QObject(parent()->object());    <--- parent() is nullptr
    QString name = toQt(q->GetAuthorUniqueId());
    if (!name.isEmpty())
        m_object->setObjectName(name);

    m_id = QAccessible::registerAccessibleInterface(this);
}

The bug can be reproduced with the sample project added to the ticket. On MacOS the accessibility can be easily triggered e.g. with the accessibility zoom feature. What I usually do is zooming in the super screen with the scroll gesture and then open a window or menu, which will cause a crash of the application.

Our crash logs also show that the bug happens on Windows.