Navigating to a Diffusion commit, and selecting the option to edit that commit, can in some circumstances bring you to the edit page for a descendant of that commit.
To reproduce:
Create a Diffusion repository. Make two commits directly via `git`, (`...a1`) and (`...b2`). `b2` is `HEAD` and `a1` is its parent.
Navigate to `/r....a1`. Select "Edit Commit". Note that the browser navigates to `/diffusion/.../commit/...a1/edit/`
But the breadcrumbs show <Diffusion Icon> -> <Repo Name> -> `...b2`. Editing the fields and hitting save does indeed modify `...b2`, not `...a1` as expected.