Is Add parallel text/Mult. books display broken in non-bibles?

So, I am trying to figure out multiple books display (MBD) in a Bible Dictionary. Since the new toolbar came out, it doesn't seem to work right.

To review: in a Bible, there is Add Parallel Text under View, to select the bibles that will show (multiple books display) with the open bible:

However, at least on Bible dictionaries, that menu item does not exist!

So does that mean Multiple book display does not work in Bible Dictionaries? No! When I brought up the Catholic Bible Dictionary, it shows 3 dictionaries in its panel! I must have set this up in a prior version of Verbum/Mac:

If I type Command-Shift-M (Mac), it still toggles the multi-book display on and off, so I see the two other dictionaries disappear or re-appear:

My problem is, where/how do I configure which resource will show up? My only options seem to be to use these options in the multiple book display, or none at all, since I have no "Add Parallel Text" menu item! Is there some way I can get the option to add/remove books from this MBD?

I am on 39.0 beta 3 Verbum/Mac.