If you import a mesh with LODs and assign the LOD Group for Foliage the mesh will import with all appropriate LODs. If you do not select a LOD group and after decide you want to change the LOD Group via the mesh editor the LODs that were present are now removed leaving the material slots available, but unable to assign any materials as well.
1. Open UE4
2. Import a mesh with LODs (use attached if needed)
3. Check the import options for import LODs
4. Uncheck the option for Combine Mesh
5. LOD Group set to None
6. Import Mesh
7. Select and open mesh in Mesh Editor
8. You will see three LODs
9. Go to LOD Group and change this to Foliage
10. You will see the other two LODs disappear
Expected: When changing the LOD group to foliage the LODs will not be wiped.
Results: The LODs disappear after changing the LOD group to Foliage. The material IDs will remain and the these are able to be seen via the details panel in the viewport for the LOD mesh.
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