Reproduction steps:
1. Open attached "New Unity Project 88".
2. Open "Scene/Scenarios/Scenario 01" scene.
3. Notice a tent surface("Picture1" attached).

Reproduced with:
* 5.4.0b22, 5.4.0b23
Not reproducible with:
* 5.4.0b21

Looks like cause is the built-in "render forward into depth" shader using VP matrix, but ShaderForge shader code using UNITY_MATRIX_MVP (instead of the new UnityObjectToClipPos function). Creates a depth precision mismatch.