### 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
HBoxContainer *top_menu = memnew(HBoxContainer);
	add_child(top_menu);
	theme_name = memnew(Label);
	theme_name->set_text(TTR("Theme:"));
	theme_name->set_theme_type_variation("HeaderSmall");
	top_menu->add_child(theme_name);
	top_menu->add_spacer(false);
	Button *theme_save_button = memnew(Button);
	theme_save_button->set_text(TTR("Save"));
	theme_save_button->set_flat(true);
	theme_save_button->connect("pressed", callable_mp(this, &ThemeEditor::_theme_save_button_cbk).bind(false));
	top_menu->add_child(theme_save_button);
	Button *theme_save_as_button = memnew(Button);
	theme_save_as_button->set_text(TTR("Save As..."));
	theme_save_as_button->set_flat(true);
	theme_save_as_button->connect("pressed", callable_mp(this, &ThemeEditor::_theme_save_button_cbk).bind(true));
	top_menu->add_child(theme_save_as_button);
	top_menu->add_child(memnew(VSeparator));
	Button *theme_edit_button = memnew(Button);
	theme_edit_button->set_text(TTR("Manage Items..."));
	theme_edit_button->set_tooltip_text(TTR("Add, remove, organize and import Theme items."));
	theme_edit_button->set_flat(true);