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.
Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response
Is this still an issue in the latest version? If so, please add a comment or update the affected version field.
To make your bug report as effective as possible, please try and include the following steps to reproduce the problem:
If your ticket does not look like the example given here, then it's likely to be closed as incomplete.
This ticket will automatically reopen when you reply.
Quick Links:
📓 Issue Guidelines – 💬 Mojang Support – 📧 Suggestions – 📖 Minecraft Wiki