When barrier blocks are used in structures saved in structure blocks, they don't show up when the "Show invisible blocks"-button is "ON". I know the barrier block shows when you hold it in your hand, but the name of the button makes me expect that the barrier block shows when it is "ON".
Edit: I saw another post reporting the same, but I don't know how to remove this.
Environment
Windows 10,
Duplicate of MC-102220.