I was tired of my daughter spilling juice every time she grabbed a juicebox and slightly squeezed it. I made this juice box holder that supports the juice box and gives handles for the user without putting pressure on the juicebox, thus preventing small spills.
It is currently scaled for juice boxes with 40x50x100mm dimensions but could be scaled easily in any dimension to match the other sizes.
There is the windowed version you see as well as a solid version in the 3mf for even more protection.