### 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
} else { 
					tab_container->move_child(tab_container->get_tab_control(tab_container->get_current_tab()), new_index);
				}
			}
		}
		tab_container->set_current_tab(new_index);
		_update_script_names();
	}
}
void ScriptEditor::input(const Ref<InputEvent> &p_event) {
	
	
	
	
	if (EDITOR_GET("interface/editor/mouse_extra_buttons_navigate_history")) {
		const Ref<InputEventMouseButton> mb = p_event;
		
		
		
		if (mb.is_valid() && mb->is_pressed() && is_visible_in_tree()) {
			if (mb->get_button_index() == MouseButton::MB_XBUTTON1) {
				_history_back();
			}
			if (mb->get_button_index() == MouseButton::MB_XBUTTON2) {
				_history_forward();
			}
		}
	}
}
void ScriptEditor::shortcut_input(const Ref<InputEvent> &p_event) {