Rated 1 out of 5 stars

a useful addon from the perspective of my browser :), I mean, yes, indeed, my browser acknowledges all these links were visited, but how about my trackers? Are they viewing the same number of visited links? Or they view only the links I have visited for real?

Besides, I checked this addon within the current FF version and it doesn't show like the extension is actually working, doing anything ... maybe I am wrong. Then how do I check if the addon is working? Thank you :)

This review is for a previous version of the add-on (3.4.2.1-signed.1-signed). 

This add-on works by adding links to the browsers history only, the links are not followed. As far as other add-ons are concerned, they probably cannot tell the difference.

You can tell if the add-on is working by looking at the history.
If the links are not showing visited, make sure Firefox's privacy settings are set to 'Remeber History' and that the layout.css.visited_links_enabled option is set to true.