Broken: 2.80 (sub 47), 0ba143a1d675, 2019-03-08 01:37
2.79 too. So perhaps not a bug but just not working.
Short description of error
Baking ignore recipient`s custom normals and use regular instead
Exact steps for others to reproduce the error
Bake from Donor To Recipient. Hide Donor.
Then connect normal map (shading tab)
Then clear custom normals data and you will see that normal map fits.