Disclaimer: Firefox sec eng who works on both this feature and Facebook Container ...
The new 2.x release of Facebook Container allows people to use "Log in with Facebook". To do so, it adds the site into the Facebook Container so sub-resources and 3rd-party cookies are available to the Facebook SDK js.
It warns the user before they enable this on any site.
Thanks for your work! When I said Multi-Account Containers are great for Power Users, I had in the back of my mind that Facebook Containers are great for everyone who does not use MAC - it really is a pretty seamless experience, and as opposed to MAC, does not require manual container selection.
The new 2.x release of Facebook Container allows people to use "Log in with Facebook". To do so, it adds the site into the Facebook Container so sub-resources and 3rd-party cookies are available to the Facebook SDK js.
It warns the user before they enable this on any site.