third-party-web/lib/markdown/updates/2021-01-01.md

Categorized data on third party entities on the web.

Due to a change in HTTPArchive measurement which temporarily disabled site-isolation (out-of-process iframes), all of the third-parties whose work previously took place off the main-thread are now counted _on_ the main thread (and thus appear in our stats). This is most evident in the change to Google-owned properties such as YouTube and Doubleclick whose _complete_ cost are now captured.