behind!
When "view background image" is greyed out, this add-on is there to help you.
behind! can reveal:
- Background images,
- Images under layers of nonsense (e.g. clickable surfaces designed to hide the image from you),
- Embedded images / base64-encoded image chunks,
- Alternative resolutions ,
- Vector images (even when they are inlined),
- Images in shadow DOM
Link to the Firefox addon page
Link to the Chrome extension page