This is something that Mozilla plans on doing in future Firefox builds, where in later releases, Firefox will block ad trackers by default. Prior to this, users would have to manually opt-in for tracking protection. This means that users will no longer need to fiddle around with the settings and will be protected when they download the app.
This is similar to what Apple has done with Safari, where the browser now blocks ad trackers by default, a move which seemed to upset many in the advertising industry. According to Mozilla who explained their reasons behind doing this, “This is about more than protecting users — it’s about giving them a voice. Some sites will continue to want user data in exchange for content, but now they will have to ask for it, a positive change for people who up until now had no idea of the value exchange they were asked to make.”