If your full-page screenshot fails on a very long page (or looks cut off), it’s usually not “your computer being slow”.

It’s a browser image limit.

TL;DR

The limit is based on total pixels (width × height × DPR²).
Best fix: make the browser window narrower before capturing.
For long documents, consider exporting PDF instead of a single huge PNG.

The real reason: total pixels

Browsers have safety limits for how large a single image (canvas) can be. A full-page screenshot is one huge image, and the limit is based on the total number of pixels:

image width × image height × (device pixel ratio²)

On 4K/5K screens, your Device Pixel Ratio (DPR) is often higher, which makes the final pixel count grow fast.

The best fix (works surprisingly well)

Make your Chrome window narrower before capturing.

That reduces the screenshot width, which dramatically increases how tall the final image can be before the browser hits its limit.

Practical tip: resize Chrome to roughly “document width” (like an A4/Letter reading column), then try full-page capture again.

Other fixes that help

Close memory-heavy tabs and try again (less RAM pressure).
If the page is dynamic, wait for it to finish loading before capturing.
If content loads while scrolling, increase Scroll Delay in Lliben settings.

When to export PDF instead of PNG/JPG

If you want a print-friendly result (and you’re capturing something very long), exporting as PDF can be a better fit than creating a single giant PNG.