To use the pop-up menu in the breakpoint view, position your mouse
  pointer in the breakpoint list or annotation area of the breakpoint
  view, and press MB3.
  A pop-up menu with the following items appears:
  Toggle                 Toggles a selected breakpoint.
  Set/Modify...          Provides the Set/Modify Breakpoint dialog box,
                         which contains information about a selected
                         breakpoint.
  Cancel                 Removes a selected breakpoint.
  Step                   Step to next line, stepping over routine calls.
  Go                     Resume execution of program.