The HTML the crawler actually gets

6 March 2026

AngularFront-endSEOSSR/SSG

What was the situation

The portfolio has a Lighthouse SEO report on purpose. How is the same kind of site: public pages, SSG, no CMS. I still opened dist/ once and found a note page whose body was an empty app root. The title was fine. The article was not there. A crawler would have ranked a shell.

That is a different bug from "forgot the resolver". The resolver can write tags while the route still prerenders a spinner because the markdown was not in the build yet, or getPrerenderParams returned nothing, or the fallback tried to render on a host that cannot.

You have to look at the HTML the crawler gets. Not the Chrome tab after hydration.

When does this apply

Use this when you ship a public Angular site and you care about search or share cards.

After adding a note, a route, or a new mainTag.
When Slack or iMessage shows the home card on a deep link.
When Lighthouse SEO is green but Google is still storing a generic title.

Skip this on authenticated product UI. There is no crawler you owe a body to.

How is it done

Build, then open the file. Do not negotiate with the running dev server. Dev still has JavaScript. The crawler often does not wait.

bash

npm run build

npm run build

For How, a note should exist as static HTML under the slug. Open that file and search for three things:

The <h1> and a paragraph from the note, not just <app-root>
rel="canonical" and og:url with https://how.athreya.codes/...
JSON-LD that names the article, not a leftover WebSite graph from home

If the body is missing, the prerender list is wrong. getPrerenderParams has to run against the same markdown the client will read. Generate that list in prebuild, not in a later job.

async getPrerenderParams() {  return inject(Posts).all.map((post) => ({ slug: post.slug }));}

async getPrerenderParams() {
  return inject(Posts).all.map((post) => ({ slug: post.slug }));
}

Unknown slugs should 404. PrerenderFallback.None plus a 404 route that is itself prerendered. A fallback that "tries later" on Firebase Hosting becomes a blank page with a 200. Search engines love a 200.

Social cards: paste the URL into a debugger when you can, but the file is the source of truth. If og:title in the file is the home title, the resolver did not run for that path.

Watch out for

Do not trust a green Lighthouse run on localhost:4201. That session had JavaScript. Run Lighthouse on the built files or on production.

Do not leave index, follow on the 404 page. That page will rank for typos.

And if you add a note and forget to run the content script, prerender will bake last week’s slug list. The new URL 404s until the next full build. That is why prebuild runs content.mjs before ng build.