Reproduction steps:
1. Open the “NaNPosition“ project
2. Open the “Sample” scene
3. Enter Play Mode and observe the Console

Expected result: No errors
Actual result: “transform.position assign attempt for 'Main Camera' is not valid. Input position is { NaN, NaN, NaN }.” error is flooded

Reproduced in: 2.9.2 (2021.3.30f1), 2.9.7 (2022.3.8f1), 3.0.0-pre.7 (2023.1.11f1, 2023.2.0b7, 2023.3.0a2)
Not reproduced in: 2.9.1 (2021.3.30f1)

Reproduced on: MacOS 13.4.1 (Intel)
Not reproduced on: No other environment tested

Note: Not reproduced in Player

Full error:
transform.position assign attempt for 'Main Camera' is not valid. Input position is { NaN, NaN, NaN }.
UnityEngine.Transform:set_position (UnityEngine.Vector3)
Cinemachine.CinemachineBrain:PushStateToUnityCamera (Cinemachine.CameraState&) (at ./Library/PackageCache/com.unity.cinemachine@2.9.7/Runtime/Behaviours/CinemachineBrain.cs:966)
Cinemachine.CinemachineBrain:ProcessActiveCamera (single) (at ./Library/PackageCache/com.unity.cinemachine@2.9.7/Runtime/Behaviours/CinemachineBrain.cs:744)
Cinemachine.CinemachineBrain:ManualUpdate () (at ./Library/PackageCache/com.unity.cinemachine@2.9.7/Runtime/Behaviours/CinemachineBrain.cs:447)
Cinemachine.CinemachineBrain:LateUpdate () (at ./Library/PackageCache/com.unity.cinemachine@2.9.7/Runtime/Behaviours/CinemachineBrain.cs:402)