### Godot version

3.5.1mono

### System information

windows10

### Issue description

Error message
 scene/main/node.cpp:1362 - Index p_index = 0 is out of bounds (data.children.size() = 0).
 scene/main/node.cpp:397 - Parameter "p_child" is null.
 scene/gui/tab_container.cpp:593 - Index p_current = 0 is out of bounds (get_tab_count() = 0).
See "Steps to reproduce for details"

### Steps to reproduce

Set an external text editor
Create a script
Drop the script to the built-in text editor like this image:
![image](https://user-images.githubusercontent.com/119792950/209504041-039f2620-5e42-4c0f-8c41-cd24486fb3d2.png)
And got error message:
 scene/main/node.cpp:1362 - Index p_index = 0 is out of bounds (data.children.size() = 0).
 scene/main/node.cpp:397 - Parameter "p_child" is null.
 scene/gui/tab_container.cpp:593 - Index p_current = 0 is out of bounds (get_tab_count() = 0).

### Minimal reproduction project

An empty project
}
		if (!edited_res->is_built_in()) {
			Ref<TextFile> text_file = edited_res;
			Ref<Script> scr = edited_res;
			if (text_file != nullptr) {
				_save_text_file(text_file, text_file->get_path());
				continue;
			}
			if (scr.is_valid()) {
				clear_docs_from_script(scr);
			}
			EditorNode::get_singleton()->save_resource(edited_res); 
			if (scr.is_valid()) {
				update_docs_from_script(scr);
			}
		} else {
			
			const String scene_path = edited_res->get_path().get_slice("::", 0);
			if (!scenes_to_save.has(scene_path)) {
				scenes_to_save.push_back(scene_path);
			}
		}
	}
	if (!scenes_to_save.is_empty()) {
		EditorNode::get_singleton()->save_scene_list(scenes_to_save);
	}
	_update_script_names();
	EditorFileSystem::get_singleton()->update_script_classes();
}
void ScriptEditor::apply_scripts() const {