I followed the links and ended up at the App Store and a price of $9.99. I am still trying to figure out the "free" part.

I think I will wait and see if the Dictionaries return in MacOS 10.13.4 Public Bata 2.

By the way I am hitting more and more compatibility and slowdownwarnings (Apples polite way of saying 32 bit). Mostly third party non-App Store support utilities such as Fujitsu's ScanSnap, H&R Block 2017 tax program, Dymo label printing software, a couple of games no longer on the App Store, and other admittedly obscure device support apps. I have contacted the developers and they are all scrambling. A couple have sent new releases with notes asking me to let them know if I still get the warning.

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein