Codespaces with fork and main repo

[MurbiesWalto]

I have a repository in my company's organization that I properly forked into my own profile.

I've been working successfully from a codespace created for the main repo so I wanted to migrate my workflow to the fork and possibly duplicate my daily-to-daily workflows.

Specifically, for smaller updates or chores, I'd skip creating a PR and push directly to upstream/master.

For some reason, I can't get this to work on the codespace created off my fork repo.

I tried using the customization for multi repos

"customizations": {
    "codespaces": {
        "repositories": {
            "insight-architectures/insight-architectures.github.io": {
                "permissions": "write-all"
            }
        }
    }
}

but I still cannot fetch or push from/to the main repo.

So I wonder if this is even supposed to work.

Thanks!