The object selection tool can be used to edit objects that are not a part of the actual PDF content. Below is a list of the objects that can be selected.
Click on the Object Selection icon on the toolbar, then click or drag an area with the mouse to select the desired objects. Once selected objects can be edited, moved, or deleted just the same as you would anything else.
To exit the selection mode, simply click on the hand tool or Esc on the keyboard.