Label positioning on link between 2 ports (nodes) not working

[BuzzyLizzy]

Followed the basic demo example, the label does not work it is not on the line of the link between the 2 nodes, but in the top left corner of the canvas, here is my code, exactly that of the demo:

import createEngine, { DiagramModel, DefaultNodeModel, DefaultLinkModel } from '@projectstorm/react-diagrams';
import * as React from 'react';
import { CanvasWidget } from '@projectstorm/react-canvas-core';
import { DemoCanvasWidget } from '../helpers/DemoCanvasWidget';

export default () => {
    //1) setup the diagram engine
    var engine = createEngine();

    //2) setup the diagram model
    var model = new DiagramModel();

    //3-A) create a default node
    var node1 = new DefaultNodeModel({
        name: 'Node 1',
        color: 'rgb(0,192,255)'
    });
    node1.setPosition(100, 100);
    let port1 = node1.addOutPort('Out');

    //3-B) create another default node
    var node2 = new DefaultNodeModel('Node 2', 'rgb(192,255,0)');
    let port2 = node2.addInPort('In');
    node2.setPosition(400, 100);

    // link the ports
    let link1 = port1.link<DefaultLinkModel>(port2);
    link1.getOptions().testName = 'Test';
    link1.addLabel('Hello World!');

    //4) add the models to the root graph
    model.addAll(node1, node2, link1);

    //5) load model into engine
    engine.setModel(model);

    //6) render the diagram!
    return (
        <DemoCanvasWidget>
            <CanvasWidget engine={engine} />
        </DemoCanvasWidget>
    );
};

[BuzzyLizzy]

I can additionally add that I am getting this error in the Chrome inspector:

Uncaught TypeError: Cannot read properties of null (reading 'getTotalLength')
    at LabelWidget.tsx:43:1
    at Array.map (<anonymous>)
    at LabelWidget.findPathAndRelativePositionToRenderLabel (LabelWidget.tsx:43:1)
    at LabelWidget.calculateLabelPosition (LabelWidget.tsx:67:1)

[BuzzyLizzy]

I found the problem, I wrapped the diagram inside this:

.... the diagram ..... when I removed that it started working correctly.

[sovetski]

I found the problem, I wrapped the diagram inside this: .... the diagram ..... </React.StrictMode> when I removed that it started working correctly.

This is not a good solution, you should keep it: https://react.dev/learn/keeping-components-pure#detecting-impure-calculations-with-strict-mode