ember-sortable bug

controllers.application.js

import Controller from '@ember/controller';
import { later } from '@ember/runloop';

export default Controller.extend({
  appName: 'Bug ember-sortable',
  columns: [
      { title: 'AAAAA' },
      { title: 'BBBBB' },
      { title: 'CCCCC' },
      { title: 'DDDDD' },
      { title: 'EEEEE' }
    ],
  
//   didInsertElement() {
//     this._super(...arguments);
//     later(this, this.addData, 5000);
//   },
  
//   addData() {
//     this.set('columns', []);
//   },
  
  actions: {
    reorderColumns(newOrder) {
      this.set('columns', newOrder);
    },
    
    removeFromColumns(meta) {
      const newList = this.columns.filter((d) => d.title !== meta.title);
      this.set('columns', newList);
    },
  }
});

styles.app.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

.thumb {
  display: inline-block;
  position: absolute;
  right: 0;
  width: 2rem;
  text-align: center;
  cursor: pointer;
}

li {
  display: block;
  background-color: lightgrey;
  width: 10rem;
  position: relative;
}

li:hover {
  background-color: lightblue;
}

templates.application.hbs

<h1>{{appName}}</h1>

The list
<br>
{{#if columns}}
  {{#sortable-group tagName='ul' model=columns onChange=(action 'reorderColumns') as |group|}}
    {{#each group.model as |column|}}
      {{#group.item class='editable' model=column as |columnItem|}}
        <button class='remove-key' {{action 'removeFromColumns' column}}>x</button>
        <span title={{column.title}} class='title'>{{column.title}}</span>
        {{#columnItem.handle class='thumb'}}⇕{{/columnItem.handle}}
      {{/group.item}}
    {{/each}}
  {{/sortable-group}}
{{else}}
Fetching data....
{{/if}}

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-sortable": "2.1.1"
  }
}