In today's reality, Internet privacy is a constant struggle as you never seem to actually achieve it unless you go through some extraordinary lengths in its pursuit. The guys from Mozilla are striving to make things better and they've recently introduced a privacy-related feature called Tracking Protection into the Beta version of Firefox. This function works on Windows, Mac, Linux and Android devices and, if everything goes according to plan, it will soon be introduced to the mainstream version of the popular browser.
As you probably already know, whenever you use the Private Mode on Mozilla your computer will be free of any traces of your online activity, but unfortunately, third-parties can still use various methods to track your browsing patterns, then sell or use the information for advertising purposes. The newly introduced Tracking Protection (which will only work along with the Private Browsing Mode) stops any webpage element which includes a code designed to track you from loading, effectively stopping it from reaching your PC.
Unfortunately, I didn't have time to test the feature yet, so I can't tell you if it actually impedes ones' regular activities, but from what I've read so far it's actually pretty good. As I said before, Tracking Protection only works while you're browsing in Private Mode, so you won't be able to use it constantly which can be seen as downside. If you want to test this new function by yourself, you will need to install Firefox Beta (which will remove your regular Firefox, so be careful), then open a new window in Private Mode and you should see message stating that Tracking Protection is ON whenever you launch a new tab.