New Twiddle

components.my-component\.js

import Component from '@glimmer/component';
import { inject as service } from '@ember/service';
import { action } from "@ember/object";

export default class extends Component {
  @service myService;
  
  // constructor(owner, args){
  // 	super(owner, args);
  //   this.myService.foo = 'init';
  // }
  
	// Using `constructor` instead of `did-insert`
	// will not re-render `this.myService.foo`
	// outside of the component
  
  @action
  init(){
    this.myService.foo = true;
    console.log("🍤 init: this.myService.foo", this.myService.foo);
  }
  
  @action
  willDestroyNode(){
    this.myService.foo = false;
    console.log("🍤 willDestroyNode: this.myService.foo", this.myService.foo);
  }
}

controllers.application\.js

import Controller from '@ember/controller';
import { tracked } from "@glimmer/tracking";
import { action } from "@ember/object";
import { inject as service } from '@ember/service';

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

	@action
	toggleShow(){
  	this.showComponent = !this.showComponent;
  }
}

routes.application\.js

import Route from '@ember/routing/route';

export default Route.extend({
  async model(){
  	await new Promise(resolve => setTimeout(resolve, 1000));
  }
});

services.my-service\.js

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

export default class MyService extends Service {
  @tracked foo;
}

styles.app\.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

.app {
	border: 1px solid black;
  padding: 10px;
}

.component {
	border: 1px solid blue;
  padding: 10px;
}

templates.application-loading\.hbs

<MyComponent />
wediu

templates.application\.hbs

<div class="app">
  <button {{on "click" this.toggleShow}}>toggle component</button>
  <br>
  <br>
  <b>this.myService.foo:</b> {{this.myService.foo}}
  <br>
  <br>
  {{#if this.showComponent}}
    <MyComponent @myService={{this.myService}}/>
  {{/if}}
</div>

templates.components.my-component\.hbs

<div class="component" {{did-insert this.init}} {{will-destroy this.willDestroyNode}}>
  <i>Within component</i>
  <br>
  <br>
  &nbsp;&nbsp;&nbsp;&nbsp;
  <b>this.myService.foo:</b> {{this.myService.foo}}
</div>

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": {
  	"@ember/render-modifiers": "1.0.2",
    "@glimmer/component": "1.0.0"
  }
}