Targeted structure voids are not visibly highlighted when Outline Selection is on

When outline selection is inactive, structure voids will be highlighted via brightening as with all blocks. However, with it on, it does not produce the expected gray "wireframe cube" you should end up getting from this block.

Expected behaviour would be for it to be highlighted respectively regardless of the setting.

Even better would be for it to only be targetable if the structure void itself is held.