System Information
Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: GeForce GTX 780/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 417.35

Blender Version
Broken: version: 2.80 (sub 64), branch: master, commit date: 2019-05-13 16:17, hash: rB0264d8390fa2
Worked: version: 2.80 (sub 60), branch: blender2.7, commit date: 2019-05-03 21:09, hash: rBee0d8426ab6d

Short description of error
When sculpting on multires modified object the drawings are not visible. Only when exiting sculpt-mode, changing the geometry data or switching to flat shaded will the new sculpting strokes become apparent. Something seems wrong with updating normals in the viewport.

Steps shown in this video (less than a minute)

Exact steps for others to reproduce the error
Create a uv-sphere (or any other object), add the multires modifier, add some subdevisions, e.g. 5 or 6 subdevisions.
Set the shade to smooth and try to draw on the sphere.