OK, I figured it out.
This is a function of Ancestry and not FTM.
I remember seeing this index when the 1940 census first come out. Yes, the index is very useful, but I had never tried copy and pasting it.
Yes, I am able to copy and paste from BOTH of the viewers, but the older one is a lot simpler to use and can see what is selected. The new viewer one just clicks and drags and hope that they have all selected.