In addition to Privacy Badger, I’ve been using Privacy Possum since I read gHack’s article on the extension. Both extensions are privacy-oriented, tracker blockers. The Electronic Frontier Foundation maintains Privacy Badger, and GitHuber user cowlicks maintains Privacy Possum.
Some have described the latter being superior to the former, and I believe they both are good tools. In my use however, Privacy Badger has had the advantage for one main reason: it can block third-party, analytics tools like Google Analytics.
This is important when we consider fingerprinting. As we know, there are multiple manners in which to fingerprint users like through their browser and operating systems. Google Analytics and other tools should be viewed similarly because they also have the potential to fingerprint by collecting user agents and cookie-specific information.
Privacy Badger is able to block Google Analytics whereas Privacy Possum has not been able to do so, and that’s okay. I would argue that the two have overlapping but different use cases. Privacy Badger appears to be able to block any response-based trackers, those that make the browser request information from their servers before sending it back. Privacy Possum more readily blocks third-party cookies because no configuration is needed as well as etag tracking, which is used similarly as cookies, and browser fingerprinting.
Still, if the browser makes a request to Google Analytics and passes its user agent and cookie-specific information to the tool, Privacy Possum currently cannot block it. You would have to use Privacy Badger or an adblocker such as uBlock Origin to do this. I would recommend to use both and to not abandon either in the favor of the other if the described tracking methods concern you.