I installed the Haskero plugin into VS Code as per the instructions there. I then followed the steps outlined in https://gitlab.com/vannnns/haskero/blob/master/client/doc/installation.md, or specifically Steps 5 and 6 as I already had a Stack project built in that directory. VS code starts up and it opens the project folder. When I hover over a function for example it shows the signature for that function, but when I select "Go to Definition", after thinking for a bit, it returns "No definition found for XXX". This is even when the definition is in the same file. For types, the hover displays nothing at all.
P.S. What puzzles me is that I don't recall anywhere associating ghc with the VS Code project so I am curious as to how it knows which compiler to use?