Sounds that you have the Bookmarks sidebar open: View > Sidebar > Bookmarks (Ctrl+B)

Firefox has two bookmark buttons with a star in the Customize window.
One star button has a drop-marker that open the Bookmark menu and may appear on the Navigation Toolbar or on the Bookmarks Toolbar if the menu bar is hidden.
The other star button without the drop-marker opens the bookmarks in the sidebar (View > Sidebar > Bookmarks).

You can drag the Bookmarks menu button with the drop-marker in the Customize window from the toolbar palette on a toolbar (e.g. Navigation Toolbar or Tab Bar or to the left side of the Bookmarks Menu Items).
If you do not see the drop-marker then try them both to see which works.

Note that you need to hide the Firefox menu bar to prevent hiding this toolbar button.

• https://support.mozilla.org/kb/How+to+customize+the+toolbar

Having a similar problem except that when I went to version 27, my bookmarks dropdown suddenly shifted from a dropdown in the center to some kind of sidebar on the right while the main page is squished left. It's very hard to read that way and annoying as all get out. I'm looking for some way to put it back where I can see.

Also looking for some way to find out about these idiotic changes -before- they happen instead of watching in terror every time Firefox says there's a new update. The "what's new" list is either not showing any more or they've fixed the search so it won't come up. I can see the point of security fixes but the last 20 versions or so have been more like malware than anything positive.

Hi desinia

Which Firefox locale (language) do you use?

Can you attach a screenshot?

• http://en.wikipedia.org/wiki/Screenshot
• https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

Use a compressed image type like PNG or JPG to save the screenshot.