Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: GeForce RTX 2080 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 430.86
Broken: version: 2.80 (sub 74), branch: master, commit date: 2019-06-05 13:55, hash: rB806d4fbc5e40
Short description of error
Since now enabling the fake user button doesn't add to the user count, the option to duplicate a datablock clicking on that number is missing for meshes. I've noticed that other data-blocks, like materials or particle systems have a button next to the fake user to duplicate the data-block. This is not the case with mesh data-blocks.
This makes duplicating meshes difficult (or it may be needed to duplicate the object and delete it afterward), so I guess the option to duplicate should be also present in the mesh data-blocks, for consistency.
Attaching examples of how it looks like.
Exact steps for others to reproduce the error
Try to duplicate a mesh data-block from the mesh tab in the Properties Editor.