Depenent Key Bug

controllers.application\.js

import Controller from '@ember/controller';
import { tracked } from '@glimmer/tracking';
import { dependentKeyCompat } from '@ember/object/compat';
import { action } from '@ember/object';

class Record {
  _currentState = { isNew: true }
  @tracked _stateNotify = 0;

  getState() {
    this._stateNotify;
    return this._currentState;
  }

  @dependentKeyCompat
  get currentState() {
    return this.getState();
  }
  
  @dependentKeyCompat
  get isNew() {
    return this.currentState.isNew;
  }
}

export default class ApplicationController extends Controller {
  records = [new Record()];
  

  @action
  updateTracked() {
    Promise.resolve().then(() => {
      this.records[0]._currentState = { isNew: false };
      this.records[0]._stateNotify++;
    });
  }
}

templates.application\.hbs

<h1>Welcome to the chain</h1>
<br>
<ul>
{{#each this.records as |record|}}
  <li>{{if record.isNew 'is-new' 'is-not-new'}}</li>
{{/each}}
</ul>
<button {{on 'click' this.updateTracked}}>Update App Name</button>
<br>
{{outlet}}
<br>
<br>

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}