Unlike Safari, Firefox doesn’t block all third party cookies by default (because that breaks some websites’ legitimate use cases). Firefox does block known trac

Unlike Safari, Firefox doesn’t block all third party cookies by default (because that breaks some websites’ legitimate use cases). Firefox does block known tracking cookies (with its “Enhanced Tracking Protection” Block list) and the remaining cookies are sandboxed to each website (“Total Cookie Protection”), so the Google tracking cookies on foo.com don’t know about the Google tracking cookies on bar.com.