New Twiddle

controllers.application.js

import Ember from 'ember';
import {task, timeout} from 'ember-concurrency';

export default Ember.Controller.extend({
  done: false,
  didSomething: task(function * () {
    this.set('done', false);
    yield timeout(5000);
    
    // here we know nothing had called didSomething for 5 seconds.
    this.set('done', true);
  }).restartable(),
  init() {
    this._super(...arguments);
    
    document.addEventListener('mousemove', () => this.didSomething.perform());
    this.didSomething.perform();
  },
});

templates.application.hbs

<h1>Welcome</h1>
<br>
Done: {{done}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2",
    "ember-concurrency": "0.8.22"
  }
}