Do you have a post you want to go back to? You can add a shortcut.
Here's how to add a shortcut to your posts:
At the very top of every post, there is a link that says "Add Shortcut".
Click on Add Shortcut and it will save the post to your shortcuts.
To find your shortcuts:
Click on "My Groups" or "My Activity" in the gray bar at the top of your page.
On the right under "My Groups" you will see "My Shortcuts".
This will show you all the posts you have made shortcuts to.