Cannot apply a global theme for the whole window.

[KynixInHK]

When I download a global theme and apply it in settings --> appearance --> global themes, it is only applied for windows' borders instead of the whole window. So is there anyone can tell me how I can apply it for the whole window? The screenshot is below. Thank you very much!

[Screenshot] https://i.ibb.co/TPSxz4v/Screenshot-20221103-185515.png