How to reproduce:
1. Open the attached “IN-92127” project
2. Open the “DecalNormalBug” scene
3. Observe the decal in the Game view
4. In the Project window, select “Assets/Materials/Decal.mat”
5. In the Inspector, set the “Normal Blend” field to 1
6. Observe the decal in the Game view

Expected result: There are no NaN artifacts
Actual result: There are clear NaN artifacts around the edges of the decal, where the decal’s normal is pointing in the negative z-direction

Reproducible in: 6000.0.12f1, 6000.0.33f1, 6000.1.0b1
Not reproducible in: 2021.3.47f1, 2022.3.55f1, 6000.0.11f1

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Note: Also reproducible in Player