Render just html string

global

<template>
  <h1>Hello {{ msg }}</h1>
</template>

<script setup lang="ts">
import { ref } from 'vue';
const msg = ref<string>('world');
</script>

Open Sandbox

with toast option

toast('Hello world.\n I am <strong>jack</strong>', {
  dangerouslyHTMLString: true, // can override the global option
});