Operating system: Windows-7-6.1.7601-SP1 64 Bits
Graphics card: GeForce GTX 980/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 425.31
Broken: version: 2.81 (sub 16), branch: master, commit date: 2019-11-20 14:27, hash: rB26bd5ebd42e3
Short description of error
"Assign Material Slot"-Shortcut is created in the wrong place, therefore does not work.
Exact steps for others to reproduce the error
By rightclicking, the shortcut is created in the Input Preferences under 3D-View > Object Mode > Object Mode (Global) which is wrong. It simply does nothing in Object mode. In order to work it has to be manually created under 3D-View > Mesh > Mesh (Global) with the same entry name.