Recently german reporters founded a mocking company claiming to be interested in dealing with "Big-Data". Several Companies offered to sell data and even provided samples of data that included the surfing behaviour of 3M german citizens. Read the Source (german): https://goo.gl/LrKmMx
"In the searches of the NDR a browser extension of the company "Web of Trust" (WOT) occurred. WOT offers a service that is designed to help the user navigate securely: the extension checks the integrity of web pages, evaluates pages visited by a traffic light system with regard to security. In the background, however, the extension also logs and transmits the data for the surfing behavior of the user to a server abroad. A profile is created where the date, time, location and controlled web address are stored together with a user ID. These data then go to intermediaries. From one of these intermediaries, Panorama and ZAPP got their record." (via google translate). My recommendation is to immediately deinstall this plugin and leave an additional feedback for it. The Plugin has a lot of positive reviews, because this facts were probably not known to the people reviewing it.
This Add-On is great! It works as I expected it to, it helps anyone know the reputation of a site before they view it which is very useful for preventing downloading of malware/virus etc. I like all features of it and I will continue to use it as it's a useful Add-On for anyone who doesn't want to download malware or viruses.
I like and appreciate the years and years of community build up. While people are generally dumb there is a certain wisdom in large/innumerable groups. That adds that extra little something to determine if a site is safe, trustworthy or not, etc.