Operating system: Win 7
Graphics card: 1060 gtx
Broken: 2.80 Beta
(example: 2.79b release)
(example: 2.80, edbf15d3c044, blender2.8, 2018-11-28, as found on the splash screen)
Short description of error
Batch generate previews does not finish the job. It does not save the new blend file with the data previews.
Exact steps for others to reproduce the error
Based on the default startup or an attached .blend file (as simple as possible).
Create a blend file with some content. Restart Blender. Go to File, Data Previews, Batch generate previews, and use it at the file. The batch generation will fail with a item attr. = val:enum "" not found error. And the new blend file will not be saved. Means we will not have a preview for this file.