isVisible bug

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  
  vizProp: Ember.computed("isVisible", function(){
    let viz = this.get("isVisible");
    return viz === undefined ? "undefined" : (viz === null ? "null" : viz);
  })
  
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

templates.application.hbs

{{my-component}}

templates.components.my-component.hbs

<div>Visibility: {{vizProp}}</div>
<br>
{{#if isVisible}}No bug{{else}}Bug{{/if}}

twiddle.json

{
  "version": "0.10.6",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "release",
    "ember-data": "release",
    "ember-template-compiler": "release",
    "ember-testing": "release"
  },
  "addons": {}
}