What is the Manifest Digest in GitLab and how do I find out more information about the manifest?

Question

GitLab provides for a "Manifest Digest",

What exactly is the Manifest Digest, a digest of, and how do I get access to this manifest to see how it's different from other images..

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this question is a follow up to What is the GitLab "Digest" on the container registry next to the images, why is different for two duplicated images