How can I find out who my friends have added and which communities they’ve joined?

You can follow your friends’ activity using the Updates tab ( When you open the tab, you’ll see a block of filters that will allow you to choose the kind of activities you want to see.

It’s important to know that privacy settings ( apply to the Updates section as well. A page’s owner can edit the Which of my updates appear in my friends' news setting, which limits what appears in other users’ updates.
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