System Information
Operating system: Windows-10-10.0.19042-SP0 64 Bits
Graphics card: GeForce GTX 750 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 456.71
Blender Version
Broken: version: 3.0.0, branch: master, commit date: 2021-12-02 18:35, hash: rBf1cca3055776; AND ALSO 3.1.0 Alpha, branch: master, commit date: 2022-01-07 23:28, hash: rB741ed5fcd2e2
Worked: --
Short description of error
New Blender 3.0.0 asset manager outputting purple objects on thumbnails instead of properly textured ones. Error occurs on some objects and not on others. Uploaded file with selected assets that present the problem. All objects and materials are rendering correctly in viewport. All textures have been packed on the blend file.
Exact steps for others to reproduce the error
https://www.dropbox.com/s/om3ja4z9ksa4jri/Test_ISO.blend?dl=0
Select all objects, then right click Mark as Asset in Outliner.