I have numerous files with png covers. So, I would say that your conclusion is not correct.
Could you check your file prior to editing with one of the linked tools for integrity?
and then test the whole thing with an error-free file?
I have numerous files with png covers. So, I would say that your conclusion is not correct.
Could you check your file prior to editing with one of the linked tools for integrity?
and then test the whole thing with an error-free file?