The problem is that the camera preview is creating a temporary copy of the camera component, copying data, then rendering that duplicate camera. It handles skybox components as a special case. We cannot do the same for post-fx because the PostProcessingLayer component exists as part of a package, and thus cannot be referenced from the Editor.

An alternative solution was explored, which called `Camera.Render` directly rather than creating a duplicate GameObject. While this partially worked, both URP and HDRP can require additional data to render properly. Ex, TAA works over multiple frames.

While this is possible to address, it would require large scale refactoring that is not commensurate with the inconvenience of the issue. After careful consideration, we have determined that other higher-priority issues should take precedence, and we have decided not to address your issue at this time. The priority level is determined by factors such as the severity and frequency of an issue and the number of users affected by it. We appreciate your input and understanding, and please let us know if you have any other concerns or issues you would like to report in the future.