pinafore/routes/_components/timeline/LazyTimeline.html

<div class="lazy-timeline">
  {{#await importTimeline}}
    <!-- awaiting promise -->
  {{then constructor}}
    <:Component {constructor} :timeline />
  {{catch error}}
    <div>Component failed to load. Try refreshing! {{error}}</div>
  {{/await}}
</div>
<style>
  .lazy-timeline {
    width: 100%;
  }
</style>
<script>
  import { importTimeline } from '../../_utils/asyncModules'
  import { store } from '../../_store/store'

  export default {
    oncreate () {
      let { currentInstance } = this.store.get()
      let { timeline } = this.get()
      this.store.set({currentTimeline: timeline})
      this.store.setForTimeline(currentInstance, timeline, {runningUpdate: false})
    },
    store: () => store,
    data: () => ({
      importTimeline: importTimeline()
    })
  }
</script>