New Twiddle

components.x-fu.js

import Ember from 'ember';

export default Ember.Component.extend({
});

components.x-wat.js

import Ember from 'ember';

export default Ember.Component.extend({
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  toShow: 'x-wat',
  actions: {
    toggleComponent() {
      if (this.toShow === 'x-wat') {
        this.set('toShow', 'x-fu');
      } else {
        this.set('toShow', 'x-wat')
      }
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{toShow}}
<button onclick={{action 'toggleComponent'}}>toggleComponent</button>
<br>
<br>

templates.components.x-fu.hbs

fu

templates.components.x-wat.hbs

wat

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"
  }
}