julia> x = [ones(2,3) for _=1:4];  # CORRECT BEHAVIOR

julia> stack(x, dims=1) |> size
(4, 2, 3)

julia> stack(x, dims=2) |> size
(2, 4, 3)

julia> stack(x, dims=3) |> size
(2, 3, 4)

julia> y = AbstractArray[ones(2,3) for _=1:4]; # NOW THE PROBLEM

julia> stack(y, dims=1) |> size
(4, 2, 3)

julia> stack(y, dims=2) |> size # THIS IS WRONG
(2, 3, 4)

julia> stack(y, dims=3) |> size
(2, 3, 4)

julia> stack(y, dims=2) == stack(y, dims=3) # THIS IS WRONG
true