Visual Cache Viewer for Firefox
Everything you browse and do in Firefox gets stored in the cache. You can browse the cache with two ways. One way is to type about:cache in Firefox and other is to access them manually from your Firefox profile.
Firefox Cache Viewer is a free tool that provides a GUI and detailed information for your Firefox cache.
This tool can help you in identifying which images are stored in Firefox’s cache. You can sort by url, size, mime type, cache location or date and can also search for specific items.
Download Visual Firefox Cache Viewer
You can download this Firefox addon from here: Download Cache Viewer