With Hover Reader installed, you can hover your mouse over any link on a web page and it will offer a “readable” version of the target web page in a preview window.
You can scroll inside the preview window with your mouse and the window disappears as soon as you move you mouse out of the window frame.
This is extremely useful for websites that contain too many links, Wikipedia for example, and you may otherwise end up having dozens of tabs in your browser. Hover Reader lets you read the target web page without opening a new tab.
Internally, the extension run the “Readability” engine on the target page thus extracting only the relevant article while stripping all the ads, graphic and other non-essential stuff.