### Godot version

4.1.1

### System information

linux

### Issue description

[simplescreenrecorder-2023-08-30_15.01.51.webm](https://github.com/godotengine/godot-proposals/assets/71937306/537d92b9-4f98-4fe6-adf4-71297be0471a)

I guess this wasn't the case before since I could save a layout named "2 monitors".

### Steps to reproduce

press space

### Minimal reproduction project

none
item_control->add_child(pin_leader_button);
				pin_leader_button->connect("pressed", callable_mp(this, &ThemeTypeEditor::_on_pin_leader_button_pressed).bind(item_editor, E.key));
			} else {
				if (ThemeDB::get_singleton()->get_default_theme()->has_stylebox(E.key, edited_type)) {
					item_editor->set_edited_resource(ThemeDB::get_singleton()->get_default_theme()->get_stylebox(E.key, edited_type));
				} else {
					item_editor->set_edited_resource(Ref<Resource>());
				}
				item_editor->set_editable(false);
			}
			item_control->add_child(item_editor);
			_add_focusable(item_editor);
			stylebox_items_list->add_child(item_control);
		}
	}
	
	if (edited_type.is_empty() || ClassDB::class_exists(edited_type)) {
		type_variation_edit->set_editable(false);
		type_variation_edit->set_text("");
		type_variation_button->hide();
		type_variation_locked->set_visible(!edited_type.is_empty());
	} else {
		type_variation_edit->set_editable(true);
		type_variation_edit->set_text(edited_theme->get_type_variation_base(edited_type));
		_add_focusable(type_variation_edit);
		type_variation_button->show();
		type_variation_locked->hide();
	}
}
void ThemeTypeEditor::_list_type_selected(int p_index) {