We sell art prints and to display them in the newsletter I need a fine hairline around the pictures. I have a CSS class for this in our shop. It is very unfortunate, that this does not work with MailPoet because it means that I have to upload all the images that are already in the Mediatek again. I love Mailpoet especially because I can use the prictures in the Mediatek. I would be very happy if I could use my own CSS soon.