[austinpena]

Depends how pages are generated. If they are using getStaticProps this is not true because the HTML needs to be "hydrated" with the React runtime which requires javascript. Astro will prebuild the static pages.

Look for a tag like this: <script id="__NEXT_DATA__" type="application/json">

[undefinedzero]

The page will render perfectly fine before it is hydrated when using getStaticProps. To verify , simply run LightHouse in Chrome on a page with cache busting on and look at the screenshot timeline. It will render in a fraction of a second, long before React gets loaded.