Expand type information collected (:set +c), used by :all-types, :type-at, ..

When collecting type information (:set +c) GHC does not collect type information from type variables in type synonyms

type Endo a = a -> a

data types and families

data List a = Nil | a ::: List a

fixity declarations

infixr 5 :::

type class declarations

class A a where
  getA :: a

and type families.. probably other things: the feature appeared one GHC version ago so, has this just not been implemented yet?