Guide
Why does Firefox's full-page screenshot only capture the visible part?
Last updated 11 October 2026
Firefox's Save full page captures the page's document from top to bottom. When a site keeps its content inside a scrolling panel, the document is only one window tall, so the screenshot matches the visible part. Lazy-loaded sections and very tall pages cause other gaps. Each cause has its own fix.
What does Firefox's Save full page actually capture?
Firefox has a built-in Screenshots tool. Mozilla's support article gives these steps:
- Right-click an empty part of the page and choose Take Screenshot, or press Ctrl+Shift+S.
- Select Save full page in the upper right corner. Save visible captures only the area in the window.
- Click Download to save a PNG to your default download folder, or Copy to put it on the clipboard.
Firefox sizes the full-page capture from the scroll width and height of the page's window, according to the Screenshots source code. That is the area the main browser scrollbar moves through. Anything that scrolls separately inside the page is outside that measurement.
Why is my Firefox screenshot cut off on web apps and dashboards?
This is the most common cause. Many web apps, including dashboards, chat apps, email clients and admin tools, fix the page to the height of the window. The content then scrolls inside one or more panels styled with overflow: auto or overflow: scroll.
MDN's overflow reference says content beyond such an element is clipped at its padding box, and the element becomes a scroll container with its own scrollbar. The rest of the content is still in the page, and the element's scrollHeight includes it. The document's height does not. Save full page therefore captures one window's worth, and each panel shows only the rows currently scrolled into view.
A quick test: if the main browser scrollbar is missing or very short while the content scrolls, the page scrolls inside a panel.
How to fix it
- Expand the panel with temporary CSS in the Inspector, then capture it with Screenshot Node. Our guide to screenshotting a scrolling div walks through it, including the pitfalls.
- Use an extension that captures scrolling panels. Screenshot Crawler finds the panels on a page automatically and captures each at full length in one pass. Page + all panels gives one image of the whole page with each panel expanded inside it. One panel captures the panel you click, and Panels only saves each panel as a separate image.
Why are images or sections missing from the bottom of the screenshot?
Many pages load images and sections only when you scroll near them. MDN's lazy loading guide explains that the loading attribute tells the browser to defer off-screen images and iframes until the user scrolls near them. If you capture straight after the page opens, content further down may still be a blank placeholder.
The fix is to scroll to the bottom of the page and back to the top before you choose Save full page. On pages that keep adding content as you scroll, stop at the point you want captured.
Is there a maximum screenshot size in Firefox?
Yes. When a capture is too large, Firefox crops it and shows the message "Your screenshot was cropped because it was too large". The message suggests a region smaller than 32,700 pixels on its longest side or 124,900,000 pixels in total area (Firefox source).
Firefox counts device pixels when it applies this limit, multiplying the page size by the display's pixel ratio (source). On a display scaled to 200%, a page reaches the limit at about half the height it would at 100%.
On a scaled display, the Web Console command :screenshot --fullpage --dpr 1 can reach further down a long page. Firefox's developer tools documentation lists --fullpage for parts of the page outside the window and --dpr for the device pixel ratio. The command applies its size cap to the page's CSS pixels (source), and a ratio of 1 draws the image at that size. Pages taller than the cap still need capturing in sections, by dragging out one region at a time.
What about sticky and fixed headers?
A fixed element is positioned against the viewport, and a sticky element against its nearest scrolling ancestor. Screenshot tools that scroll the page and stitch the frames together can repeat these headers down the image or lay them over the content beneath. Screenshot Crawler captures sticky and fixed headers once.
Which fix matches my problem?
| What you see | Likely cause | Fix |
|---|---|---|
| Full page looks the same as Save visible | Content scrolls inside a panel | Expand the panel with CSS and use Screenshot Node, or use Page + all panels in Screenshot Crawler |
| Outer page is complete, but a sidebar or list stops early | That sidebar or list is its own scroll container | One panel or Page + all panels in Screenshot Crawler |
| Blank areas or missing images lower down | Lazy-loaded content | Scroll to the bottom and back before capturing |
| "Your screenshot was cropped because it was too large" | Size limit | :screenshot --fullpage --dpr 1 on a scaled display, or capture in sections |
| Header repeated down the image | Sticky or fixed header in a stitched capture | A tool that captures fixed headers once |
Where does Screenshot Crawler fit?
Firefox's built-in tool handles ordinary pages well, and it is the right first choice there. Screenshot Crawler is for pages where the content scrolls inside panels. It works in Firefox 142 or later and has a Chrome test build. Every capture mode is in the Free tier, and Pro is US$5, paid once. Captures are processed on your device and nothing is uploaded. Results save as PNG or PDF.
Try it
The two-panel test page holds two independently scrolling lists, rows A001 to A100 and B001 to B100, inside a dashboard with a sticky sidebar. Capture it with Save full page, then check whether rows A100 and B100 appear. Install Screenshot Crawler free from Firefox Add-ons and capture the same page with Page + all panels to compare.