The new message on my dashboard announcing that listing preview is now available has this incorrect link when you click the button to 'see what's new':
https://www.etsy.com/your/shops/RainasMagicShop/tools/listings?ref=seller-platform-mcnav
It should be probably be https://www.etsy.com/your/listings?ref=seller-platform-mcnav, so it's not specific to another shop.
@BlackSheepDyeworks: Good catch - any Etsy URL with "/your"/ or "/me/" is already specific to a logged in shop (on the back end Etsy replaces that URL segment with your shop id) so that you can only see your own data. This seems an easy thing to have been tested before publishing.