Helper Entangle Tracking Context

controllers.application\.js

import Controller from '@ember/controller';
import { inject as service } from '@ember/service';

export default class ApplicationController extends Controller {
  @service
  myService;
  
  appName = 'Ember Twiddle';
}

helpers.my-helper\.js

import Helper from '@ember/component/helper';
import { inject as service } from '@ember/service';
import { run } from '@ember/runloop';

export default class MyHelper extends Helper {
  @service
  myService;
  
  compute(params, _hash) {
    // @tracked works if push is queued with runloop
    /*run.schedule('actions', () => {
      this.myService.pushItem({
        title: params.join(""),
        ..._hash
      });
    });*/
    
    this.myService.pushItem({
      title: params.join(""),
      ..._hash
    });
  }
}

services.my-service\.js

import Service from '@ember/service';
import { tracked } from '@glimmer/tracking';

export default class MyService extends Service {
  //@tracked
  items = [];

  pushItem(item) {
    this.items = [...this.items, item];
  }
}

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

{{my-helper "My title"}}

{{#each this.myService.items as |item|}}
	{{item.title}}
{{/each}}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}