I am implementing tools within the SceneView using the UnityEditor.Overlays API. One of my overlay (MeshEditor) is docked underneath the built-in tools overlay. However, the size of the overlay area, for lack of a better term, is driven by the maximum width/height of any overlay docked within it.
Because of this, even though you click on an empty space within the overlay area, which should count as a SceneView click, the overlay system eats the input and it is never sent to the SceneView.
In the GIF below, you can see, the tooltip for the overlay appearing as soon as I enter the empty space underneath the built-in tools overlay. You can also see in the console whenever the MouseDown event is actually sent to the SceneView, along with the rect selection being processed.
You can also see the issue being fixed as soon as I undock the overlay from the built-in tools one. According to me, the overlay area should not process mouse events if it is over an empty space in the overlay container. Is this the inteded behaviour?