### Godot version

4.1 rc3

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

This™
![image](https://github.com/godotengine/godot/assets/2223172/cb33110f-a5b0-400a-951f-3fa425f05714)

It can still happen, but it's more difficult to trigger.

### Steps to reproduce

1. Create a new scene with a Control node
2. Add Theme to the Control
3. Open Theme Editor
4. Clear the `theme` property in Control
5. Save, with Theme Editor opened
6. Restart

### Minimal reproduction project

N/A
}
		}
		for (int i = 0; i < vsplits.size(); i++) {
			bool in_use = dock_slot[i * 2 + 0]->get_tab_count() || dock_slot[i * 2 + 1]->get_tab_count();
			if (in_use) {
				vsplits[i]->show();
			} else {
				vsplits[i]->hide();
			}
		}
		bottom_panel->show();
		if (right_l_vsplit->is_visible() || right_r_vsplit->is_visible()) {
			right_hsplit->show();
		} else {
			right_hsplit->hide();
		}
	}
}
void EditorNode::_restore_floating_dock(const Dictionary &p_dock_dump, Control *p_dock, int p_slot_index) {
	WindowWrapper *wrapper = Object::cast_to<WindowWrapper>(p_dock);
	if (!wrapper) {
		_dock_make_float(p_dock, p_slot_index, false);
		wrapper = floating_docks[floating_docks.size() - 1];
	}
	wrapper->restore_window_from_saved_position(
			p_dock_dump.get("window_rect", Rect2i()),
			p_dock_dump.get("window_screen", -1),
			p_dock_dump.get("window_screen_rect", Rect2i()));
}
void EditorNode::_load_docks_from_config(Ref<ConfigFile> p_layout, const String &p_section) {