SparseMatrixCSC + Zeros returns dense matrix

[blegat]

julia> x = sparse([1, 2], [1, 2], [1.0, 2.0])
2×2 SparseMatrixCSC{Float64, Int64} with 2 stored entries:
 1.0   ⋅ 
  ⋅   2.0

julia> y = FillArrays.Zeros{Float64}(2, 2)
2×2 Zeros{Float64}

julia> x + y
2×2 Matrix{Float64}:
 1.0  0.0
 0.0  2.0