Right now, we've set Tor Browser to block third party cookies. This will probably break some sites. There is a less intrusive option described at https://wiki.mozilla.org/Thirdparty that we should use. **Rebase** and test existing patches (originating from https://bugzilla.mozilla.org/show_bug.cgi?id=565965) **Revise requirements** according to preliminary tests and devise a broad test plan. **Reimplement and retest** to guarantee proper isolation without severely impeding cookie dependent applications. **Document** the implementation and optionally a contrast of browser cookie handling. Pave the way towards a **improved privacy panel** including a new cookie inspector and API supporting such UI. ---- **Note:** This is a metaticket composed of work items in child tickets.