How to reproduce:
1. Open the attached “IN-130727.zip” Project
2. Enter Play Mode
3. Observe the Console Window

Actual result: “Trying to set shader on a Material Variant” error is constantly printed
Expected result: No errors are printed

Reproducible with: 3.0.5 (6000.5.0a5)
Not reproducible with: 2.4.3 (6000.0.66f2), 3.0.5 (6000.0.66f2, 6000.3.6f1, 6000.4.0b6), 3.0.5 (6000.5.0a5)

Notes:
- Reporter also noted that 6000.3.3.f1, but could not get a local reproduction on any other stream versions after downgrading/deleting library folder
- Downgrading and upgrading fixes the issue
- Considering the testing method and how to workaround the issue, it would appear that it originates from a corrupted library, however it is unclear how it got to that state.
- Full error message:
Trying to set shader on a Material Variant.
UnityEngine.Material:set_shader (UnityEngine.Shader)
Unity.PolySpatial.Internals.MaterialTrackerBase`3/MaterialApplier<UnityEngine.MeshRenderer, Unity.PolySpatial.Internals.PolySpatialRenderData, Unity.PolySpatial.Internals.TrackingData`1<Unity.PolySpatial.Internals.PolySpatialMeshRendererTrackingData>>:CopyMaterialAndApplyPropertyBlocks () (at /Users/bokken/build/output/unity/polyspatial/Packages/com.unity.polyspatial/Runtime/Trackers/MaterialTrackerBase.cs:74)
Unity.PolySpatial.Internals.MaterialTrackerBase`3/MaterialApplier<UnityEngine.MeshRenderer, Unity.PolySpatial.Internals.PolySpatialRenderData, Unity.PolySpatial.Internals.TrackingData`1<Unity.PolySpatial.Internals.PolySpatialMeshRendererTrackingData>>:Update (UnityEngine.Renderer,int) (at /Users/bokken/build/output/unity/polyspatial/Packages/com.unity.polyspatial/Runtime/Trackers/MaterialTrackerBase.cs:67)
Unity.PolySpatial.Internals.MaterialTrackerBase`3/PropertyBlockApplier<UnityEngine.MeshRenderer, Unity.PolySpatial.Internals.PolySpatialRenderData, Unity.PolySpatial.Internals.TrackingData`1<Unity.PolySpatial.Internals.PolySpatialMeshRendererTrackingData>>:Update (UnityEngine.Renderer) (at /Users/bokken/build/output/unity/polyspatial/Packages/com.unity.polyspatial/Runtime/Trackers/MaterialTrackerBase.cs:175)