### 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 (p_resource.is_null()) {
		return false;
	}
	Ref<Script> scr = p_resource;
	
	bool use_external_editor =
			EDITOR_GET("text_editor/external/use_external_editor") ||
			(scr.is_valid() && scr->get_language()->overrides_external_editor());
	use_external_editor = use_external_editor && !(scr.is_valid() && scr->is_built_in()); 
	const bool open_dominant = EDITOR_GET("text_editor/behavior/files/open_dominant_script_on_scene_change");
	const bool should_open = (open_dominant && !use_external_editor) || !EditorNode::get_singleton()->is_changing_scene();
	if (scr.is_valid() && scr->get_language()->overrides_external_editor()) {
		if (should_open) {
			Error err = scr->get_language()->open_in_external_editor(scr, p_line >= 0 ? p_line : 0, p_col);
			if (err != OK) {
				ERR_PRINT("Couldn't open script in the overridden external text editor");
			}
		}
		return false;
	}
	if (use_external_editor &&
			(EditorDebuggerNode::get_singleton()->get_dump_stack_script() != p_resource || EditorDebuggerNode::get_singleton()->get_debug_with_external_editor()) &&
			p_resource->get_path().is_resource_file() &&
			!p_resource->is_class("VisualScript")) {