Firefox 90 SmartBlock 2.0: The most important surveillance protection offered by browsers is the Private Browsing feature, which is an anonymous browsing mode that often prevents third parties, even the browser itself, from monitoring your Internet traffic. This privacy measure is not perfect and sometimes interferes with functionality.
The new SmartBlock 2.0 for Firefox 90 promises to protect your privacy even in the most demanding services like Facebook.
Just like Google, Facebook offers one-on-one or SSO features that allow you to create new accounts on other services through Facebook. This feature often uses cookies, which precludes Firefox's private browsing feature. Things get even more complicated because Facebook is on the list of known Disconnect trackers that Firefox uses to identify the scripts of sites it should block.
Unfortunately, this puts some sites in disarray especially those who use Facebook to facilitate subscription to their services. These include Etsy, Pinterest and others. On these sites it is quite annoying or even impossible for users to connect to safe browsing. In other words, Firefox users used to have to choose between protecting their privacy or using these sites.
SmartBlock 2.0 will help you as it can connect you to these sites without sacrificing your privacy. Private browsing in Firefox still blocks all Facebook scripts, but when it detects a Facebook connection, it only unlocks the login script so you can continue as normal.
This exception only works for Facebook Links to Private Browsing.