System Information
Operating system: Linux-5.4.73-1-lts-x86_64-with-arch 64 Bits
Graphics card: GeForce RTX 2070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 455.38
Blender Version
Broken: version: 2.83.13, branch: master, commit date: 2021-03-09 07:21, hash: rBbb5004673085
Short description of error
The mesh and armature have a scale 1 and rotation 0
The shoulder bone named "Def_shoulder.L" has a huge weight deform on the object.
Normally shoulder should not deform the jaw because I have put a jaw bone.
Also It will not deform head, neck and arm !
Exact steps for others to reproduce the error
Open
Select object "Bust" and shift select armature Ctrl + p > Automatic Weight
Uncheck Lock Object Modes
In pose mode select the shoulder bone "Def_shoulder.L" and shift select the object "Bust" and Ctrl tab > Weight paint to see the weight deform