If you mean the mail slot, it’s perhaps old-fashioned, since it’s a security weakness.
I remember seeing an old movie where a family kept the house key on a string just inside, so when the kid got home from school they could reach in, get the key, and unlock the door (parents were at work).
And a couple where someone put fire or explosives through the slot.
Pick up a box on sale and put it in the cupboard. It’s a useful base for some chicken pieces, or to make some vegetables into a casserole. Excellent with mushrooms. (Take into account the liquid that will be released by the cooking veggies, or else saute them first, before mixing with the stuffing)
This year, instead of a whole bird, I made Turkey Balls using 2 lbs ground turkey, 2 raw eggs, stuffing mix, then sauteed onion, celery, apple, mushrooms, (let cool before adding) Chardonnay, and cool broth. I added the usual spices, keeping in mind there’s already some in the stuffing. I piled them in a lidded casserole, but you can also bake them on a sheet pan and serve with dips.