[fixed] Models from .obj files don't show up anymore

[micheus]

mik_igra, thanks for checking.

Those ignored "Ka" and "Kd" are no critical and should not represent the cause of the issue you are experiencing. (they should be related to the ignored material, since they represents the ambient and diffuse colour of a material). By ignoring it the 'default' material is used as replacement.

the .obj is loaded you can select something, but you don't see what you have selected, its blank, how could i make it visible again?

I read better this sentence and I have to ask you: Since you says it loads and some selection seem do be done, did you try, in Body selection mode, use the command "Invert" and see if something changes for you?

In which application these .obj files were generated? Any chance it has get an update and been exporting the .obj incorrectly?

If you load it in this online viewer (https://3dviewer.net/), did you see it correctly?

Also, could you share a screenshot of you geometry window.
It's very hard to try help without know what you are seeing once the issue is eventual and not reproducible on my side.