http://kittens.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/issues/do-not-track-archived
These headers include information like what browser you're using, what language your computer is set to, and other technical details. The Do Not Track signal is a machine-readable header indicating that you don't want to be tracked. Because this signal is a header, and not a cookie, users can clear their cookies at will without disrupting the functionality of the Do Not Track flag.