Operating system: Linux-5.7.6-arch1-1-x86_64-with-glibc2.29 64 Bits
Graphics card: AMD KAVERI (DRM 2.50.0, 5.7.6-arch1-1, LLVM 10.0.0) X.Org 4.5 (Core Profile) Mesa 20.1.2
Broken: version: 2.83.1, branch: makepkg (modified), commit date: 2020-06-25 09:47, hash: rB8289fc688b3e (I've got it from pacman)
Worked: I haven't checked this exact function on other versions so, unknown
Short description of error
Assigning materials on faces of an object breaks the model and doesn't work properly.
Exact steps for others to reproduce the error
I've created a sphere with a material 001. Than I've selected certain faces of this sphere and applied material 002 on them:
That's a result of applying the material: faces I've selected disappeared and there is something broken inside. That's what I saw when selected certain faces:
As you can see, this broken black thing changed its shape and colored itself in material 002.
Now then I've selected other rings that were in material 001 previously and assigned and assigned material 003 on them.
Surprisingly, they were colored to material 002
That's what happened when I've assigned material 004 on other selected rings (those rings I've applied the material on are selected in the picture)