Old GoJS go object loaded: 1.8.38. Replaced with version: 1.8.38

found the answer, I was trying to use one of the extensions (LinkLabelDraggingTool).
which cause this,

anyway I could not find a way to use it in my angular application
I tried :

diagram.toolManager.mouseMoveTools.insertAt(0, new LinkLabelDraggingTool());

and I a get this error
error-handler-delegate.service.js:33 Error: value is not an instance of Tool: LinkLabelDragging Tool
at Object.k (go-debug.js:32)
at Object.mc (go-debug.js:33)
at K.oh (go-debug.js:69)
at K.insertAt.K.be (go-debug.js:75)

Yes, the error message is saying that you are loading the GoJS library more than once.

How are you loading the LinkLabelDraggingTool?

using system.js
using its mapping

in my component I use
import {LinkLabelDraggingTool} from “gojs/extensionsTS/LinkLabelDraggingTool”;

Maybe how the tool is importing go.js conflicts with how you are importing go.js:

import * as go from '../release/go';

You might find it easiest to just copy the tool code into your own source files.

copying it works fine,
BUT I do not want to do that, because I do want to get the new changes

The alternative is to modify the extensionsTS/LinkLabelDraggingTool.ts file to import the GoJS library the same way that the rest of your app does.

Or maybe it would help to change the extensionsTS/tsconfig.json file to target es6 instead. Then you would just need to recompile the TypeScript sources.