(I work for Mozilla. Not speaking for Mozilla here.)

January 28, 2019:

Male impotence, substance abuse, right-wing politics, left-wing politics, sexually transmitted diseases, cancer, mental health....Intimate and highly sensitive inferences such as these are then systematically broadcast and shared with what can be thousands of third party companies, via the real-time ad auction broadcast process which powers the modern programmatic online advertising system. So essentially you’re looking at the rear-end reality of how creepy ads work.

—Natasha Lomas, on TechCrunch

Also January 28, 2019:

Simply put: users need more protection from tracking....In support of this effort, today we are releasing an anti-tracking policy that outlines the tracking practices that Firefox will block by default. At a high level, this new policy will curtail tracking techniques that are used to build profiles of users’ browsing activity. In the policy, we outline the types of tracking practices that users cannot meaningfully control.

—Steven Englehardt and Marshall Erwin, on the Mozilla Security Blog

https://blog.zgp.org/perfect-timing/