Extended C# custom types aren't detected by the editor

[olexatourko]

Godot version

3.3.3

System information

Ubuntu 20.04

Issue description

I added a custom type with a plugin using AddCustomType. The custom type appears in the node selector as expected and shows the icon.

However when I extend the node with a new script, the editor looses the type/icon information in the extended node. BT_Task is the custom type added by the plugin, and BT_Task2 is using a script that extends the type. It looses the icon, and when i hover it it says its of type Node instead of BT_Task.

I'm not sure if this is actually a bug or not but I can't find anything in the docs about it. I expected that I could just extend custom types the same way that i can base types. Also I'm not sure why the custom type still shows a script icon beside it.

Steps to reproduce

Create a C# custom type via plugin and then try to extend a node of that type.

Minimal reproduction project

No response

[olexatourko]

Any node with a script that extends a custom type seems to be completely disconnected from that custom type. For example,

public class BT_InspectorPlugin : EditorInspectorPlugin
{
	public override bool CanHandle(Godot.Object @object)
	{
		GD.Print(@object.GetType());
		return (@object is BT_Task);
	}
}

Just shows Godot.Node for the custom type i'm trying to extend. Is custom type inheritance simply not a thing?

Edit Okay; the extended script is picked up in the logic above of I give it the [Tool] attribute. I assumed it'd detect the attribute from the base script. Unfortunately the type and icon still aren't correct in the node tree however.

[piratesephiroth]

I guess this should be included in #44879/#48201