How to reproduce:
1. Open the “ReproProjectNavMesh“
2. Open the “Export“ scene
3. Open the “Navigator“ GameObject in the Inspector
4. Under the NavMesh Surface component Clear the baked NavMesh
5. Bake a NavMesh with the current settings
6. In the AI Navigation overlay toggle on the Show HeightMesh property
7. Observe the Scene view

Expected result: No streaks/spikes of Height Mesh are crossing the entire scene
Actual result: Streaks/Spikes of Height Mesh are crossing the entire scene

Reproducible with: 1.1.5 (2022.3.42f1), 2.0.3 (6000.0.15f1)
Could not test with: 1.0.0-exp.4 (2021.3.42f1) (Could not resolve the Console errors)

Reproducible on: macOS 14.5 (Intel), Windows 11 (Reporter’s)
Not reproducible on: No other environments tested

Note: The issue reproduces with both adding the “com.unity.ai.navigation“ as an embedded package, and downloading it from the registry