Here's a good tip. Instead of creating more clutter, pin your opened food packets that's not finished on your fridge with magnets. Redditor dewder recommends hanging it inside your fridge with a magnet.

No space on the door? No sweat. dewder mentions that you can actually use them inside your fridge, too:
This is baby food, which you have to use in 24 hours or throw away. Also, the packet it comes in does not stand up in the fridge. So rather than lay it flat and have it pour out, lean it up against something that will just fall over, all on top of having to pin or clip it closed, you just take a magnet, fold over the top, stick it to the inside, et voila, all problems solved.