Two clarifying points: 1. This is a technical proposal. It has not been incorporated into Firefox; I don't think there are even patches for it at this point.

Two clarifying points: 1. This is a technical proposal. It has not been incorporated into Firefox; I don't think there are even patches for it at this point. 2. Safari actually already implements a different technology designed to achieve somewhat similar objectives. https://webkit.org/blog/11529/introducing-private-click-measurement-pcm/ https://webkit.org/blog/11529/introducing-private-click-meas...