Imagus

The extension is intended to complement image features that (I think) is missing from Opera by default or give features that are just simply useful. Hover zoom ...

Free Mac Windows Linux Chrome Safari ... Maxthon Opera Firefox

Thumbnail Zoom Plus

The free Thumbnail Zoom Plus add-on for Firefox shows the full image when you hover over a thumbnail or image link. Supported sites include Amazon, Bing, Facebook...

• Discontinued The extension is not compatible with Firefox 57. It still works on XUL-based Firefox forks like https://alternativeto.net/software/waterfox/ and https://alternativeto.net/software/palemoon/

Free Open Source Mac Windows Linux Pale Moon Firefox

ezLinkPreview

Browse more efficiently: Preview links and images without leaving your current tab. Mouseover any link and click the 'ez' icon (or press ALT and mouseover link)...

Free Mac Windows Linux Chrome

Hover Zoom

Enlarge thumbnails on mouse over. Works on many sites (Facebook, Twitter, Flickr, Reddit, Amazon, Tumblr, etc).

• Warning As written at http://www.reddit.com/r/technology/comments/1t4ubn/hoverzoom_for_chrome_is_infected_with_malware/ , it seems to contain malware. Be careful!

Free Mac Windows Linux Chrome OS Chrome

Hover Zoom+

Hover your mouse over any image on the supported websites and the extension will automatically enlarge the image to its full size, making sure that it still fits into...

Free Open Source Mac Windows Linux Chrome Firefox

ImagePreviewer

Opis This extension shows a popup with an image preview when hovering over link that points to an image file or a page with an image. This extension uses...

Free Mac Windows Linux Opera

Image Preview (Chrome extension)

Finds links to images and youtube videos in the web page you're on and replaces the link with a lightbox popup.

Free Open Source Mac Windows Linux Chrome

Zoom

A browser extension that zoom in the current open webpage with a slide.

Free Open Source Mac Windows Linux Chrome OS Chrome ... Safari Opera Firefox

Image Preview (Firefox addon)

Preview image when mouse over image link.

• Discontinued The extension is not compatible with Firefox 57. Last version, 0.0.11.1, released in January 2015, still works on XUL-based Firefox forks like https://alternativeto.net/software/waterfox/ and https://alternativeto.net/software/palemoon/

Free Open Source Mac Windows Linux Pale Moon Firefox

ImageZoomer

Zoom images inline on the current page by holding the right mouse button and scrolling the mouse wheel. How to use: * Hold the right mouse button on an image...

Free Mac Windows Linux Chrome

Thumbnail Zoom

Shows a full size image when you hover over thumbnails on popular websites like Facebook, Twitter or Amazon. The addon shows a floating panel with the full size of a...

Free Open Source Mac Windows Linux Firefox