When I wanted to inspect Docker-Container that existed in a remote Docker-registry, I normally used skopeo:

skopeo inspect docker://ubuntu:latest
{
    "Name": "docker.io/library/ubuntu",
    "Digest": "sha256:9a0bdde4188b896a372804be2384015e90e3f84906b750c1a53539b585fbbe7f",
    "RepoTags": [
        "10.04",
        "12.04",
        "12.04.5",
}

This command show me all the information about the image that I needed …

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