Depth buffer problem when doing grab pass

I am trying to make a feature. I do a grab pass before a camera rendering, and then render the grab texture on screen after the camera rendering, so that i can make the whole camera rendering transparent. It works in editor, but when i build it to iOS. it gets a weird depth problem. It’s like the app capture the depth in the first frame, and use it as cleared depth. The result looks like there is an invisible model cut through objects

I have same problem, and I found this only happened when msaa is enabled. But still don’t know how to prevent it.

I found this issue is similar to my case, but this issue fixed in preview for 2 years, still not release, any one knows what happed?