this add-on intent is to popup a full-size image or video file when you hover the mouse over a link to such, saving you a click. very helpful for media-rich but shallow news / discussion sites such as Reddit.
** when the add-on is first added you will need to refresh any already loaded pages to see effects.
** if you're not seeing as many popups as you'd like try placing a single period '.' into the Scrape List and empty the Scrape List Block boxes on the options page to check every mouseover for media.
- dynamically load image content with specific site handlers
- photo albums, navigation via mouse wheel & arrow keys
- load MP4 video in place of animated GIF when available (smaller, faster)
- add links with shown popups to browser history (optional)
- minimal, small footprint
source : https://github.com/unarj/hooverZoom