.. in head
<script type="module>">
import { auObserver, defaultConfig } form './html-au/dist/browser/js/index.js';
import { HelloMsg } from './hello-msg.js'
customElements.define('hello-msg', HelloMsg);
auObserver(document.body, defaultConfig)
</script>
... in body
<button tf-trigger='click' tf-ced='post hello-msg' tf-target="main" tf-swap='innerHTML' name='msg' value='Hello World'>Show Message</button>
<main></main>
// returns
<main><hello-msg>Hello World</hello-msg></main>