Missing client tailored IDP SSO metadata

Hi, I am trying to set up a Keycloak development IDP for my Ruby on Rails API, but I gut stuck on retrieving the IDP metadata for the client I have created.
I am spawning with docker compose a keycloak 19.0.3 dev mode with a postgresql db.
I have created a saml client and I figured the client tailored IDP xml should be inside the zip file that you can download at Action > Download adaptor configs > Mod Auth Mellon files.
The problem is the downloaded zip file cannot be opened. I have tried to create multiple clients, but I end up with the same issue. Any idea what’s wrong?

Many thanks!