Move `PopupMenu` item to desired index (inside the menu)

Godot Version

v4.4.1.stable.official [49a5bc7b6]

Question

For the plugin I am making now, I need to add an option to the FileSystem’s right-click context menu. After I successfully adding my option as the method provided by this GitHub comment, I try to move my newly added option to the desired place, but I failed to do that.

I have tried move_child, but that does not seems to work, the item seems to be internal.

Could I ask if there is a way of re-ordering the item in the PopupMenu ?

Code example (part copied from the GitHub comment mentioned above):

@tool
extends EditorScript

static func add_custom(popup: PopupMenu):
	# All other item are added, so this item will be at the last.
	popup.add_item("Test", 10000)
	# How could I move it up ?

func _run() -> void:
	var fs = EditorInterface.get_base_control().find_child("*FileSystem*", true, false)
	var popup: PopupMenu = fs.get_child(2)
	popup.about_to_popup.connect(add_custom.bind(popup), CONNECT_DEFERRED)

I don’t see any way to do that in the PopupMenu API. Most of it uses the index of the element to interact with them.

Thank you. Maybe I should write a proposal at GitHub for adding a method to expose the internal structure of item array (or something else) ?