Plugin created in addons sub-subfolder is detected, but class_name nodes & resources don't show in Create New Node/Resource dialogue

Godot version

4.0.3.rc2.official.2ac4e3bb3

System information

Ubuntu 22.10, Vulkan, NVIDIA GeForce RTX™ 2060 / NVIDIA GeForce RTX™ 2060

Issue description

Custom (class_name) nodes & resources don't show up in Create in New Node/Resource dialogues.

This came up because I was looking at Godot Project Manager which uses NPM as a the packager and delivery mechanism. With NPM we can use scoped names like @scope/package and they get installed at addons/@scope/package.

They're detected by Godot just fine, it's just that the custom nodes and resources don't appear in the dialogues as mentioned.

Steps to reproduce

Top Level plugin is in addons/top_level
Nested Level plugin is in addons/@scope/nested_level

Open the attached project and see that:

Plugins ON => TopLevel* visible, NestedLevel* not visible
Plugins OFF => TopLevel* not visible, NestedLevel* not visible

in Create New Node/Resource.

Furthermore, it seems that we have access to the classes in code even if the plugins are ON or OFF. I thought they should be registered globally only when plugins are ON.

Minimal reproduction project

godot-4-dbg.zip

Further context https://github.com/godot-package-manager/cli/issues/29

godotengine / godot