Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: GeForce GTX 1080/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 417.71
Broken: version: 2.80 (sub 60), branch: master, commit date: 2019-04-29 10:32, hash: rBa57fec986d2d
Worked: (optional) 2.79b
Short description of error
UV Sculpt tools seem to have no effect at all.
Exact steps for others to reproduce the error
Start Blender. Make a Grid. Set it to 50x50
Go to the UV workspace
Select the Pinch, Relax or Grab tools and click and drag around the UV space. Nothing will happen.
Do the same thing in Blender 2.79b and the UV mesh will be deformed.