Use brilliant workaround to show Windows 10 top border

Sine Striker

2023-12-24 46285db399f75154ad6c451e12f2cae2e59ace25

 examples/mainwindow/mainwindow.h

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

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

    Theme currentTheme{};