Positive tiff conversion: placement in stack not working

In the settings for a positive copy of version 2.3.0, it is now possible to include the positive copy in collections, which is great help (thank you Nate). However, the option to stack the copy with its original doesn’t seem to work. When I choose that option, the copy is not stacked with the original and it always appears at the end of the collection, so that I have to manually stack the two images. For larger collections, this is really bothersome, as I have to select the two images (one in the middle of the collection and the other one at the end of the collection) and then stack them manually. It would be great if stacking were working.