Comment 1 for bug 1894319

Implementation detail: on Docker Registry HTTP API V2 (https://docs.docker.com/registry/spec/api/), "Multiple architecture support" is marked as "future", so it is not described how to do the images upload distinguishing the different architectures there.

Although it is not documented on the API, docker client has a way to do it, and it is well explained in this blog post: https://www.docker.com/blog/multi-arch-build-and-images-the-simple-way/

The general idea seems to be creating multiple manifests (one per arch) and "merging" them together.