The scrollHeight Lie: How I Finally Got Full-Page Screenshots Right with Playwright

If you've ever tried to take a full-page screenshot of a modern website

programmatically, you've probably run into the same wall I did:

document.body.scrollHeight lies. Constantly.

The problem

Lazy-loaded images, infinite scroll sections, sticky headers, scroll-triggered

animations — all of these mess with the page's reported height in ways that

make scrollHeight an unreliable signal for "have I reached the bottom of

this page yet?"

I was building — it roasts your website with AI

and emails you three things that are actually wrong with it.

Happy to go deeper on any part of this if useful.