jsdelivr/+esm: [object Object]

https://cdn.jsdelivr.net/npm/lit-element@2.5.1/lit-element/+esm rendering: [object Object]

but https://unpkg.com/lit-element@2.5.1/lit-element.js?module work fine?

my code:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <date-hijri date="Sat May 15 2021 18:17:31 GMT+0300"></date-hijri>
<script src='https://cdn.jsdelivr.net/npm/moment@2.29.1/moment.min.js'>
</script>
  <script src='https://cdn.jsdelivr.net/npm/moment-hijri@2.1.2/moment-hijri.min.js'>
  </script>
<script type='module'>
import {html, LitElement} from 'https://unpkg.com/lit-element@2.5.1/lit-element.js?module';

export class DateHijri extends LitElement {

  static get properties() {
    return {
      date: {type: String}
    }
  }

  constructor() {
    super();
    this.date = moment();
  }

  render() {
    let date_hijri = moment(this.date).format('iYYYY/iM/iD');
    return html`${date_hijri}هـ`;
  }
}

customElements.define('date-hijri', DateHijri);
    </script>
</body>
</html>

lit / lit-element

jsdelivr/+esm: [object Object] #1197