We have a display shelf unit in our dining room that my wife has filled with her stuff. Most of it is breakable so she's worried that our soon to be walking grandsons will come and push the shelves such that they'll fall down.
They are held up with those push in flat pins:
My idea for making this not happen is to screw some small blocks of wood just in front of the rear most pins, preventing the shelf from moving backwards and coming off the front pins.
Of course my wife thinks this will ruin the furniture and thinks she'll see the blocks even though you'd have to really be looking hard to see them on the upper most shelves way at the back.
How would you secure the shelves so they wouldn't be able to be moved, yet still maintain their adjust ability?