string[] Returns the mask names defined in renderingLayerMaskNames, but with each name prefixed by its index in the array, a colon, and a space. For example, if the element with an index of 2 has the name "Example Name", its value in this array is "2: Example Name".
Returns the names of the Rendering Layer Masks for this pipeline, with each name prefixed by a unique numerical ID.
This property is useful for creating custom Editor UI for a render pipeline. If the array of Rendering Layer Mask names contains duplicate names, this property lets you distinguish them by their prefix.