“IProcessSceneWithReport.OnProcessScene” allows modifying the scene that is saved into a build or played in the editor, without modifying the scene on disk. I’d like somebody to confirm that this is indeed the intended behaviour that can be relied on, because I never found anything in the documentation indicating that’s the case.
Seems intended to me. I’m not sure what you’re looking for here exactly. No one can guarantee you that an API won’t be deprecated at some point in the future, but Unity is bound by semantic versioning. This means that for all API’s, you are assured that patch releases will only contain backwards-compatible bugfixes.
I can confirm that it doesn’t modify the scene on disk, we have a “validation” workflow that relies on IProcessSceneWithReport and tested it to confirm that.