This 6.1 version of Unity is no longer being updated. This issue may be fixed in a future version.
Reproduction steps:
1. Make sure that HDR is enabled in Windows via the Display Settings
1. Make sure that IL2CPP is installed via the Unity Hub for the Editor version that you’re going to be using
2. Open the attached “repro_IN-87680“ project
3. Open the “Assets/OutdoorsScene.unity“ Scene
4. Open the Build Profiles (“File → Build Profiles“)
5. Build the project
6. Open the built executable
7. Observe the Player
Expected result: Canvas is only rendered once - in the middle of the Player
Actual result: Canvas is rendered in each split-screen