Capture a Whole Web Page in Firefox and Check the Content Below the Fold
A full-page screenshot can document the layout of a long page for a website review. Before capturing it, decide which sections must appear and whether an image is the right record. Searchable text, linked documents and interactive controls may need separate evidence.
Prepare the actual page state
Open the intended page and note its address and capture time. Expand the sections you need, dismiss only irrelevant overlays and scroll through the content so you can recognise the beginning, middle and end. Keep a note of anything loaded only after scrolling or interacting.
Remove private account information from the page state where possible before capture. A full-page image can include personal details far below the visible viewport, so checking just the current screen is insufficient.
Right-click an empty part of the page and choose Take Screenshot. Select Save full page rather than Save visible, then download the image. Mozilla documents that the PNG goes to Firefox’s configured download location; locate that actual file before assuming it was saved somewhere else.
Inspect the complete image
Open the PNG at a readable scale. Compare a recognisable item near the top, one in the middle and the final section or footer with the live page. Look for blank image areas, repeated sticky elements, missing expanded content and truncated text.
If the result is incomplete, document which section is absent and capture that region separately. Do not label a partial image as a complete page merely because the capture option was called Save full page. A video player, dynamic list or protected page can require another form of evidence.
Keep the original image privately and review the whole shareable copy for confidential content. Add the page address, date and any deliberate omissions to the accompanying note. The acceptance check is visible coverage of the sections needed for the review; a screenshot does not preserve every interactive function or prove what the page displayed at another time.
Sources: Mozilla Support.