How do you pre-fetch data for a route in Vue 3?

Data can be fetched in the onBeforeRouteUpdate hook or by using a custom 'loader' pattern with Suspense.

To provide a seamless experience, you often want to start fetching data before the component even finishes mounting. In the Composition API, you can use onBeforeRouteUpdate to react to route changes. For initial load, most developers use onMounted or a state management action inside the router's beforeEach guard.