I have this (short for question) single file component (vue 3.2.31):

<template lang="pug">
.test Hello world!
</template>
<style lang="sass" scoped>
.test
  font-weight: bold
</style>
<script setup lang="ts">

onMounted(() => {
  console.log('Mounted');
});

</script>

It is bundled via vitejs, exported as (say) NamedExport, and imported on the client side as a base64 encoded string on demand.

const component = await defineAsyncComponent(async () => {

  // A module that exports multiple components.
  const module = await import(base64StringSentFromTheServer);

  // Choose one.
  return module['NamedExport']);

})

Then, the result must be:

<component :is="component" />

It works just fine , except for two things, one of which is that the hook is not called (in this case onMounted) and the other is that neither is the style importer is called.

Is this expected behavior, or am I missing something? Is <script setup> the way to write responsible components?