I've been hosting an image for my PayPal checkout banner using the Public folder but today it is no longer showing up on PayPal. I assume that's because the Public folders are no longer actually public. I tried moving the image file over to another folder and set the permissions to "anyone with the link" can view it. I copied the link but PayPal is rejecting it, probably because the file name ends with .jpg?dl=0 instead of simply .jpg. PayPal requires that the image be hosted on a secure server; that's why I had been using Dropbox to achieve this. What can I do to make it work again?