There should be one published when listings are published, but seems like it's not being done so properly if it's not showing up for clients that support it.
I don't really want to encourage people to use coracle for these, since I've removed a lot of support for them nostr:nprofile1qy2hwumn8ghj7am0deejucmpd3mxztnyv4mz7qg3waehxw309ahx7um5wgh8w6twv5hszrnhwden5te0dehhxtnvdakz7qgkwaehxw309a5xzan9dchxxctvwesjuer9wchsz9nhwden5te0v4jx2m3wdehhxarj9ekxzmny9uqzp5mwszpl57ekmthxgm9ck0uel64rmz095wt9pp6p7qp7yxkqk6lv9lxeyl is there a NIP 89 handler for shopstr?
Discussion
I saw the one-off one... which is a weird pattern too. Why are you doing it that way?