Edit Guide... does not work for Program Monitor Guides

With “Show Guides” turned on in the Program Monitor, right-clicking a guide and choosing “Edit Guide...” opens the Edit Guide dialog. Modifying the Position value and clicking OK does not affect the guide. Likewise, changing the Units or Orientation doesn’t have any effect on the guide. Clicking the “Left” and “Right” radio buttons results in both buttons being selected (see screen shot). They act like checkboxes rather than radio buttons. The only parameter that appears to properly affect the selected guide is Color.