When upgrading a project that was prior to the material slot implementation to a newer engine version will cause redundant material slots to be created. This requires the mesh to have LODs and multiple materials to reproduce.

Steps to Reproduce
  1. Import attached mesh with LODs and Multiple materials in a 4.13 or earlier project
  2. Notice three materials are imported
  3. Convert project to 4.14 or 4.15
  4. Open project and then asset

There are additional material slots added that are identical to the preexisting materials.

A material slot is generated for each material and no additional one are created.

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Affects Versions4.14.34.15
Target Fix4.16
Fix Commit3360369
Main Commit3379345
CreatedMar 9, 2017
ResolvedMar 23, 2017
UpdatedFeb 4, 2019
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