2.8 Beta 12-12-2018
Short description of error
When a .blend file is saved while in the Sculpt workspace, reloading the file will cause the sculpt brush cursor to disappear. Checking the menu shows that the brush should be visible. The only fix is to go back to object mode and then enter sculpt mode again. At this point, the sculpt brush cursor will reappear.
Load in the attached file. This is the Default cube that has had a SubD modifier applied to it. The Sculpt workspace was selected, a few brush strokes were applied, and the file was saved.
When you load the file, you will be in sculpt mode, but you will not see a sculpt cursor. Go back to object mode and then re-enter sculpt mode. The cursor will reappear.