You can find D3 almost everywhere on the web now, and often you’ll want to grab a visualisation to use elsewhere. In particular, you may want to capture a particular state of an interactive visualisation after playing with some parameters. Since it’s not an image per se, you can’t just right click and download it. You could print the entire page, but then you have to crop it and risk losing the resolution. Fortunately there is a solution, developed by the New York times no less, that grabs the raw SVG and downloads it for you. The bookmark is available here, and you can drag and drop it to your bookmarks bar for ease of use later. Try it on this interactive bilevel partition visualisation here. The image below shows an example output.

An SVG is a useful image format; it allows you to do further editing in Photoshop or other image editing software later, such as adding layers or changing colours. If necessary, you can convert this to a jpeg or other static formats.