i did wonder if it’s a combination of the magnets in the phone, case and MagSafe charger putting pressure on the case itself but that’s just a wild guess.
Apparently, the Apple wallet leaves an imprint on the back of the leather case after a few day's use as well so its definitely not a heating issue.
To be honest as the back off the case patina's and darkens, it will probably be less noticeable.
But as a fun experiment, I have ordered one of these and I am going to fit it on the other side of the charger so that it is in between the case and charger. if the phone still charges, the skin should provide protection for the case
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