Selection Outline/Wire missing in only one scene. Gizmo settings are correct, tried resetting layout.

Hi, selection outlines and selection wire has completely disappeared in one of my scenes. They work in other scenes but comparing the gizmo / editor color settings all scenes seem to be using the same values.

I still see the gizmos such as move when I select an object and cameras/lights icons.

Let me know which direction I should look towards to find a solution. Thanks!