### Godot version

4.0.3.stable

### System information

windows 11

### Issue description

fullscreen on the window node is not working and will show up as a windowed.

### Steps to reproduce

disable Embed Subwindows in Project Settings/Display/Window.
create a window node and set its mode to fullscreen.

### Minimal reproduction project

[fullscreen.zip](https://github.com/godotengine/godot/files/11821834/fullscreen.zip)
ERR_FAIL_COND(window_id == DisplayServer::INVALID_WINDOW_ID);
	mode = (Mode)DisplayServer::get_singleton()->window_get_mode(window_id);
	for (int i = 0; i < FLAG_MAX; i++) {
		flags[i] = DisplayServer::get_singleton()->window_get_flag(DisplayServer::WindowFlags(i), window_id);
	}
}
void Window::_clear_window() {