PyQt6-Qt6 6.12.0 (Windows): Qt Quick Controls Windows/FluentWinUI3/Native style libraries missing

[Dragan A.]

Hi Phil,

On Windows 11 x64 with Python 3.14, PyQt6 6.12.0 and PyQt6-Qt6 6.12.0 from
the
Riverbank index, QML that imports QtQuick.Controls fails to load unless a
non-native style is selected explicitly:

    import sys
    from PyQt6.QtCore import QByteArray
    from PyQt6.QtGui import QGuiApplication
    from PyQt6.QtQml import QQmlApplicationEngine

    app = QGuiApplication(sys.argv)
    for style in ("", ".Windows", ".FluentWinUI3", ".Basic"):
        engine = QQmlApplicationEngine()
        engine.loadData(QByteArray(
            f"import QtQuick\nimport QtQuick.Controls{style}\n"
            "ApplicationWindow { Button {} }\n".encode()))
        print(style or "(default)", "OK" if engine.rootObjects() else
"FAILED")

Result: default, .Windows and .FluentWinUI3 fail; .Basic works. The error
is:

    module "QtQuick.Controls" version 6.12 cannot be imported because:
    Cannot load library ...\PyQt6\Qt6\qml\QtQuick\Controls\Windows\
    qtquickcontrols2windowsstyleplugin.dll: The specified module could not
be found.

The QML plugins for these styles are in the wheel, but the libraries they
link
against are not in Qt6\bin:

    Qt6QuickControls2Windows.dll
    Qt6QuickControls2WindowsStyleImpl.dll
    Qt6QuickControls2FluentWinUI3.dll
    Qt6QuickControls2FluentWinUI3StyleImpl.dll
    Qt6QuickControls2Native.dll
    Qt6QuickNativeStyle.dll

The two *StyleImpl libraries are also missing from PyQt6-Qt6 6.10.2 and
6.11.0-6.11.2 on PyPI, so FluentWinUI3 has not loaded there either. In 6.12
the
Windows style itself moved into Qt6QuickControls2Windows.dll, so now the
default
style fails too, which breaks a plain "import QtQuick.Controls" on Windows.

Adding those six DLLs from the Qt 6.12.0 binaries to PyQt6\Qt6\bin makes all
three styles load and render correctly.

Other QML plugins in the 6.12.0 wheel also reference missing libraries:
Qt6QmlNetwork, Qt6QmlLocalStorage, Qt6QmlXmlListModel, Qt6QmlDesignSupport,
Qt6QuickShapesDesignHelpers, Qt6QuickVectorImageHelpers, Qt6PdfQuick,
Qt6Quick3DParticleEffects, Qt63DQuickScene2D and Qt63DQuickScene3D.

Could these be added to PyQt6-Qt6 before the 6.12.0 release on PyPI?

Thanks,
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