What was the solution, so someone who is searching for the same thing could find the answer here?

Original Question:

I click "Bookmarks", getting a drop down menu I click on a Group I created (NEWS, e.g.) The list of sites in that Group appear on the right of the drop down, they used to appear on the left I deleted some bookmarks, causing the list to appear on the right side - the left side is, of course, closer to my cursor, how do I get the list back to the left of the drop down?

Firefox will open a folder list to the left in case some names are too long to fit in the available screen space. You would have to shorten longer names to be able to open more folders to the right.