The user wants to express using the difference between SceneDepth and CustomDepth. However, when r.CustomDepth = 3 (Enabled with Stencil), the expression can not be realized because the SceneDepth and CustomDepth values of the same mesh are different.
This issue can not be reproduced on PC and Android. It only occurs on iOS.
expect : Black screen is displayed
result : White silhouette is displayed
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-68050 in the post.