Full screenshot of long page is incomplete

[upsuper]

For example, open https://html.spec.whatwg.org/ wait it to fully load, and try to take the full page screenshot of this page.

On my machine, it only gets to section 1.4, but the page is apparently much longer than that.

I'm on Firefox 74, and Ubuntu 19.10.

[jaredhirsch]

Screenshots uses a single canvas to capture screen contents, so the height is limited to the height of a canvas, around 32k pixels.

[upsuper]

Is it possible to capture the content into multiple images to overcome this limitation? That would probably be enough for many people.

(And with that data available, the next step could be to compile an image concatenater to wasm and run it to generate the final image.)