A handy tool that will finally mark visited links in Firefox in another colour which will prevent you from accidentally clicking on the same link again, and, will structure your research a little bit more.
You can choose any colour you like for the visited links, I chose green, and visited links will be marked with that colour.
Sometimes this is not very helpful, especially when you are reading a manual or a book or something. A short-cut ALT-V will therefore turn this visited feature on or off. Very useful.
Add-on for Mozilla Firefox. Created by 7-elephant, Thailand, last updated: 13 Sep 2015