### 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
#include "theme_editor_plugin.h"
#include "core/os/keyboard.h"
#include "editor/editor_node.h"
#include "editor/editor_resource_picker.h"
#include "editor/editor_scale.h"
#include "editor/editor_undo_redo_manager.h"
#include "editor/gui/editor_file_dialog.h"
#include "editor/progress_dialog.h"
#include "scene/gui/check_button.h"
#include "scene/gui/color_picker.h"
#include "scene/gui/item_list.h"
#include "scene/gui/option_button.h"
#include "scene/gui/panel_container.h"
#include "scene/gui/scroll_container.h"
#include "scene/gui/split_container.h"
#include "scene/gui/tab_bar.h"
#include "scene/gui/tab_container.h"
#include "scene/gui/texture_rect.h"
#include "scene/theme/theme_db.h"
void ThemeItemImportTree::_update_items_tree() {