Reproduction steps:
1. Open user's project "DebugWater.zip"
2. Make sure that you have Inspector, Frame Debug, and Game View windows opened (add them if any are missing)
3. Enter Play Mode and click "Enable" in the Frame Debug window
4. In the Frame Debug window navigate to Camera.Render/Drawing/Render.OpaqueGeometry/RenderForwardOpaque.Render/RenderForward.RenderLoopJob
5. Click on Draw Mesh LPWWaterChunk and open ShaderProperties
6. Scroll down to the Vectors section and look at the unity_OcclusionMaskSelector parameter, notice how it's (0, 0, 0, 0)
7. In the Hierarchy window, click on "Cube TouchMe" to make it appear in the Inspector window

Expected result: Nothing changes upon something appearing in the Inspector window (either the water is pinkish or purplish both before clicking and after clicking)
Actual result: unity_OcclusionMaskSelector parameter changes to (1, 0, 0, 0) and the water in the Scene turns pinkish

Reproducible with: 2020.3.9f1, 2021.1.0a1
Not reproducible with: 2021.1.0a2, 2021.1.8f1, 2021.2.0a17
Couldn't test with: 2018.4, 2019.4 (Couldn't downgrade to a functioning project)

Notes:
- Also reproducible in Edit Mode, Play Mode is needed for Frame Debugger
- Water remains pinkish until the next time you open the project