A simple print that solves a simple problem. The bracket that slides in the freezer shelf bar is 24mm tall and 6mm wide. It slides in easy and does not move around.

To install - remove the freezer shelf bar clips connecting the shelf bar to the freezer. Measure how far the shelf bar clips go into the shelf bar. Glue the printed brackets to the printed backplate to account for the shelf bar clips (I use Loctite Super Glue). Let dry and slide into the shelf bar. Done! No more falling sandwiches!!!

Made in Tinkercad. Sliced with Cura. Printed on Ender 3 V2 Neo. PLA OVERTURE filament. 

.4 Nozzle - Standard Quality .2mm - 20% infill