New Twiddle

controllers.application\.js

import Controller from '@ember/controller';
import Ember from 'ember';

export default Controller.extend({
  appName:'Ember Twiddle',
	startDate: null,
	newDates: [],
	newDate: Ember.computed.alias('newDates.firstObject') ,
	actions: {
    setDate(date) {
    	console.log(date)
  	},
    setStartDate() {
   	this.set('startDate', new Date());
 	}
  }
})

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
{{#unless startDate}}
{{ember-flatpickr date=null}}
 {{/unless}}
 <button {{action 'setStartDate'}}>Set Start Date</button>
<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": "3.6.1",
    "ember-template-compiler": "3.6.1",
    "ember-testing": "3.6.1"
  },
  "addons": {
    "ember-data": "3.4.2",
    "ember-flatpickr": "2.11"
  }
}