New Twiddle

components.test-a.js

import Ember from 'ember';

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

components.test-b.js

import Ember from 'ember';

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

controllers.application.js

import Ember from 'ember';

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

templates.application.hbs

<br>
<br>
{{test-a}}
<br>
<br>

templates.components.test-a.hbs

<div>
  {{test-b id="area"}} 
</div> 
<div id="area">
  Hello, world 
</div>

templates.components.test-b.hbs

Test-B template: id = {{id}}

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"
  }
}