System Information
Operating system: Windows-10-10.0.18362 64 Bits
Graphics card: GeForce GTX 1070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 430.86

Blender Version
Broken: version: 2.80 (sub 74), branch: master, commit date: 2019-07-11 13:50, hash: rB06312c6d2db8
Worked: (optional)

Short description of error
On opening blender, in the default scene, when I delete one of the available workspaces, then on trying to add them back from the menu bar doesn't work. That workspace is removed from the menu bar.

Exact steps for others to reproduce the error

1. Open blender. The default startup opens with the default scene.
2. In the menu bar from the available workspaces, Right-Click on one of the workspaces e.g Animation.
3. From the context menu that opens, select Delete. The workspace is removed from the menu bar.
4. Click on the Add Workspace button.
5. Then from the menu that opens, select General => [Workspace that was deleted previously]. In this case it was Animation.
6. Notice that the workspace is not added.

This is happening in the default startup.