New Twiddle

controllers.application.js

import Ember from 'ember';
import Mixin from '@ember/object/mixin';

const Foo = Mixin.create({
  handleReponse:{
    colorURL(c){
        this.clean(c);
    },
    clean(c){
      alert(c);
    },
	}
});


export default Ember.Controller.extend(Foo, {
  init() {
    this._super(...arguments);
    this.handleReponse.colorURL(12);
  },
});

templates.application.hbs

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

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"
  }
}