joicomponents/test/polyfill/f_firefox_async_upgrade/index.html

Design patterns to build native web components

<!-- load webcomponents bundle, which includes all the necessary polyfills -->
<!--<script src="https://unpkg.com/@webcomponents/webcomponentsjs@2.0.0/webcomponents-loader.js"></script>-->

<my-element></my-element>

<script src="webcomponents-loader-2.js"></script>