By bug 818340, we introduced the new option "network.cookie.cookieBehavior=3" and added the new pref GUI to preference->privacy->"Accept third party cookies: From visited". However, I think this label is not clear. The new option which is safari-like 3rd party cookie policy will send/receive 3rd party cookie if browser has (store) the their 3rd party's cookie in that time. But I think that the current label of "From visited" might mislead user. It's not clear because the "visited 3rd party" also means the domain which Firefox has some history without any cookies in his places. So I propose that we change the label text from "From visited" to "Stored only" or other suitable words. We should change it more clear words which means only the region of cookies.

The implementation is certainly to allow third party cookies only where a cookie already exists for the third party, but do we want to expose the users to that?

The current implementation of "network.cookie.cookieBehavior=3" will send/recieve the 3rd party cookies if they have been stored in browser whether or not they were stored as 3rd party in the past. I seem the current label of preference expresses that browser send/recieve 3rd party cookies if browser has been visited (and their browser history is recorded) whether their cookie is stored in browser now. I don't think this is clear. So I propose we should clear the meaning of label for informing its preferences depend on whether cookies are stored in browser or not.

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258