Select Available to display a list of selectors that are defined for the class and that are not presently loaded in the image. These selectors might be methods that were defined in alternative editions of the class or they might be methods that were previously deleted from this class edition.

When you choose a selector from the dialog box that appears when you select Available, a Method Editions Browseropens on all editions of the method. From there, you can browse and load editions of the method.