Totally fix top border issue on Win10 for QtWidgets

Sine Striker

2023-12-26 6b2d31247dc2c2804e571b31a71c8a423c1db9d4

 examples/mainwindow/mainwindow.h

@@ -28,6 +28,7 @@

private:
    void installWindowAgent();
    void installStyleAgent();
    void loadStyleSheet(Theme theme);

    Theme currentTheme{};