Operating system: Linux-4.15.0-66-generic-x86_64-with-debian-buster-sid 64 Bits
Graphics card: GeForce GTX 1050 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 435.21
Broken: version: 2.81 (sub 16), branch: master, commit date: 2019-11-08 22:59, hash: rB0a0d735acd6e
Short description of error
Material of mesh object turns to Grease Pencil material.
Exact steps for others to reproduce the error
I just created object and plug it to use in hair particle system and it's material turns to Grease Pencil material so I can not to change material properly anymore. It happens time to time.