How to reproduce it:
1. Open the user's project "UiTransparentTest.zip"
2. Open the Build settings and make sure that only the "UiToolkitScene" Scene is selected for the build
3. Build and Run on an Android device

Expected results: FPS counter in middle shows ~29 FPS when the green rectangle is visible and when it's not visible
Actual results: FPS counter in middle shows ~24 FPS when the green rectangle is visible and ~29 FPS when the green rectangle is not visible

Reproducible with: 1.0.0-preview.17 (2020.3.17f1, 2021.1.19f1), 2021.2.0b9, 2022.1.0a7
Could not test with: 2019.4.29f1 (UI Toolkit package is not supported)

Reproducible devices:
VLNQA00288, Samsung Galaxy J7 (SM-J730F), Android 8.1.0, CPU: Exynos 7 Octa 7870, GPU: Mali-T830

Not reproducible devices:
VLNQA00022, Xiaomi Redmi Note 3 (Redmi Note 3), Android 6.0.1, CPU: Snapdragon 617 MSM8952, GPU: Adreno (TM) 510
VLNQA00001, Google Pixel 2 (Pixel 2), Android 11, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540
VLNQA00316, Samsung Galaxy Note10 (SM-N970F), Android 9, CPU: Exynos 9 Series 9825, GPU: Mali-G76
VLNQA00225, Qualcomm null (SDM845 for arm64), Android 8.1.0, CPU: Snapdragon 845 SDM845, GPU: Adreno (TM) 630

Notes:
- Not reproducible on iOS or Standalone