I have Classic Theme Restorer installed, so I don't know if this will work for you, but can you click an icon (such as the downloads button) and get the toolbar back from there?

I do know with the new Firefox customize mode, you can edit things easily. You should be able to click "Show/Hide Toolbars" and drag the bookmarks toolbar back to where it's supposed to be.

• If you click "Remove this Toolbar" then you remove the button from the Navigation Toolbar and move it to the Customize palette ("3-bar" Firefox menu button > Customize).
• If you would click "move to Menu" then you move a button to the "3-bar" Firefox menu button drop-down list

If you have hidden the Bookmarks Toolbar by removing the checkmark in front of it then you can right-click empty area on the Navigation Toolbar and restore the tick to enable the Bookmarks Toolbar.

• Firefox menu button > Customize > Show/Hide Toolbars
• View > Toolbars (press F10 to show the Menu bar)
• Right-click empty toolbar area

See also:

• https://support.mozilla.org/kb/how-do-i-delete-bookmark