### 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
int selected = tab_container->get_current_tab();
	if (selected < 0 || selected >= tab_container->get_tab_count()) {
		help_overview->set_visible(false);
		return;
	}
	Node *current = tab_container->get_tab_control(tab_container->get_current_tab());
	EditorHelp *se = Object::cast_to<EditorHelp>(current);
	if (!se) {
		help_overview->set_visible(false);
		return;
	}
	if (help_overview_enabled) {
		members_overview_alphabeta_sort_button->set_visible(false);
		filter_methods->set_visible(false);
		help_overview->set_visible(true);
		overview_vbox->set_visible(true);
		filename->set_text(se->get_name());
	} else {
		help_overview->set_visible(false);
		overview_vbox->set_visible(false);
	}
}
void ScriptEditor::_update_help_overview() {