How do social plugins work?
While these buttons and boxes appear on other websites, the content populating them comes directly from Facebook. The plugins were designed so that the website you are visiting receives none of this information.These plugins should be seen as an extension of Facebook.
You only see a personalized experience with your friends if you are logged into your Facebook account. If you are not already logged in, you will be prompted to log in to Facebook before you can use a plugin on another site.
At a technical level, social plugins work when external websites put an iframe from Facebook.com on their sites, as if they were agreeing to give Facebook some real estate on their websites. When you visit one of these sites, the Facebook iframe can recognize if you are logged into Facebook. If you are logged in, it’ll show personalized content within the plugin as if you were on Facebook.com directly. Even though the iframe is not on Facebook, it is designed with all the privacy protections as if it were.
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