This is a thing with multiple vendors. Jars with magnetic lids to stick to the fridge.
https://www.amazon.com/Magnetic-Refrigerator-Hexagon-Containers-Kitchen/dp/B0DD9RR3QP/?_encoding=UTF8&pd_rd_w=MPQrX&content-id=amzn1.sym.4efc43db-939e-4a80-abaf-50c6a6b8c631%3Aamzn1.symc.5a16118f-86f0-44cd-8e3e-6c5f82df43d0&pf_rd_p=4efc43db-939e-4a80-abaf-50c6a6b8c631&pf_rd_r=Z3N2EYEA44ZHCMCMAAQV&pd_rd_wg=4lg1l&pd_rd_r=fe24ae58-91b4-4857-afd6-e7771efe5498&ref_=pd_hp_d_atf_ci_mcx_mr_ca_hp_atf_d&th=1