Reproduction steps:
1. Open the attached user's Unity project "TestOnPostRender.zip"
2. Go to Assets > Scenes folder
3. Open "SampleScene.unity" and enter the Play mode
4. Observe "Update" and "OnPostRender" in the Game view
Expected result: OnPostRender is called once per frame
Actual result: OnPostRender is called multiple times per frame
Reproducible with: 2021.2.0a2, 2021.2.19f1, 2022.1.0b15, 2022.2.0a8
Not reproducible with: 2019.4.37f1, 2020.3.33f1, 2021.2.0a1, 2022.2.0a9