How to reproduce:
1. Open the attached 'New Unity Project.zip' project
2. Build for iOS and open the Xcode project
3. Deploy the Xcode project to the iOS device

Expected result: the RawImages display the Render Texture as in Editor
Actual result: the scene is rendered in the bottom-left corner and the unity splash screen flickers in the background

Reproducible with: 2018.4.24f1, 2019.4.2f1, 2020.1.0b14, 2020.2.0a15

Reproducible with:
- Mac Standalone
- Windows Standalone
- iPhone 8 Plus (iOS 12.0)
- iPhone XR (iOS 13.4.1)
- iPad Air 2 (iOS 11.0.3)
- VLNQA00220, Samsung Galaxy Note9 (SM-N960F), Android 8.1.0, CPU: Exynos 9 Series 9810, GPU: Mali-G72
- VLNQA00123, Google Pixel 2 XL (Pixel 2 XL), Android R, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540
- VLNQA00024, Xiaomi Mi 5 (MI 5), Android 7.0, CPU: Snapdragon 820 MSM8996, GPU: Adreno (TM) 530

Notes:
- Workaround: use Graphics.SetRenderTarget instead of Camera.SetTargetBuffers
- Reproducible with Graphics APIs that support dynamic resolution Metal, Vulkan, DX12; Not reproducible on OpenGL, DX11;
- On Mac Standalone regression is introduced in 2019.2.0a1
- Screenshots of the expected and actual results are attached in Edit