What can be used to attach the pan cam to the top of the refrigerator so it doesn’t wobble off?
Adhesive backed Velcro… or that super strength 3m duo-lock.
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For a more permanent mounting solution, you can try a magnetic mount from B&H. https://www.bhphotovideo.com/c/product/862033-REG/PANAVISE_864_Magnetic_Base_Black.html