連番ダウンローダー is a powerful and straightforward image downloader designed for Firefox users. This subscription-based extension allows users to download multiple images from a webpage with a single click, saving them in a sequentially numbered format (e.g., 0.png, 1.png). Users can also select specific image ranges for downloading by dragging over them, or simply right-clicking on images for quick saving. This tool is particularly useful for accessing images on older personal websites that might not be compatible with other downloaders, making it a versatile option for various browsing needs.

The extension automatically saves downloaded images into a folder named after the page title, keeping the downloads organized. It supports a wide range of image formats including png, jpeg, gif, svg, bmp, and webp. Additionally, for certain websites such as Twitter and Imgur, it can retrieve images in their original sizes. This functionality is especially helpful for users dealing with file names that are randomly generated, simplifying the downloading process significantly.