svelte/test/runtime/samples/observe-deferred/main.html

<p ref:a>{value}</p>
<p ref:b></p>

<script>
	export default {
		oncreate() {
			this.on('update', ({ changed }) => {
				if (changed.value) {
					this.refs.b.textContent = this.refs.a.textContent;
				}
			});
		}
	};
</script>