I've heard of issues with the timeline from many people here. What I have noticed personally is that when my friends post content themselves (any content pictures videos etc) it'll show up. Also when they share someone else's content it shows up. The posts that don't show up are posts that my friends either like our comment on. The only way I know if a friend liked our commented on someone else's post is if I have that someone else as a friend as well, and even then it doesn't show up as a post itself I have to look at the original post that was liked our commented on. Also pics that show up as posts as a result of being shared on Instagram do not show up on the app either. The last type of posts that I've noticed that don't show up in the app are posts within a group that you are in but not tagged in. For example I'm part of a closed group called west Texas performance and when I had my iPhone I would see people post to the group wall often even if the person posting wasn't my friend, these types of posts do not show up on the Windows Phone app (unless I'm tagged in it of course)
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