I have two objects (from a Collada import), one can be beveled, the other not. I cannot see any differences in the mesh. I checked for non-manifold edges, I checked for the orientation of the normals, I checked for sharp edges, ... What am I missing?
The .blend file (version 2.81) can be downloaded here: https://www.dropbox.com/transfer/AAAAAP6OKinOxeC5PAGGCIZJp6WsqX2sHdYds-C1aVJGl63GLkFIH_g
Thanks in advance for any help!