Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce GTX 1070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 441.66
Broken: version: 2.83 (sub 13), branch: master, commit date: 2020-04-16 15:38, hash: rB8cb10c124efe
Worked: (newest version of Blender that worked as expected)
Short description of error
I used undo (ctrl+z) on last smooth operation and all (I believe) evected by that operation faces were removed leaving a hole.
Exact steps for others to reproduce the error
I folowed tutorial on the cloudfor stylized character. I used remesher to join all geometry and started smoothing out the model. I think I used the crease tool with both crease and cut brush and than started to smoothing it out. I attached two saves, one before and one after bug.