Problem uploading .nupkg to our dev tenant - error about missing icons

[box-turtle]

This morning I tried to upload a new .nupkg file to our dev tenant and I'm receiving the following error, which seems to be incorrect?

{
    "error": {
        "code": "ExtensionsInvalidPackage",
        "pbi.error": {
            "code": "ExtensionsInvalidPackage",
            "details": [
                {
                    "code": "Reason",
                    "detail": {
                        "type": 1,
                        "value": "InvalidParameter"
                    }
                },
                {
                    "code": "Target",
                    "detail": {
                        "type": 1,
                        "value": "MissingAssets"
                    }
                },
                {
                    "code": "Message",
                    "detail": {
                        "type": 1,
                        "value": "Certain artifacts reference images that are not found in the designated assets folder. Ensure all icons are correctly placed in the assets folder."
                    }
                }
            ],
            "exceptionCulprit": 1
        }
    }
}

The error would indicate that I am missing an asset that is referred to in either Item1.json or Product.json, but I don't think that is the case. I even tried uploading a .nupkg file that has been successfully deployed to our prod environment and it gave me the same error.

Previously we did have some image names that has underscores "_" but I changed all those to hyphens and still see the error.

Oddly I can run local dev mode and don't get any errors from the validator.

Attaching the file I am trying to upload for reference:

WorkloadManifest_staging.nupkg.zip

[box-turtle]

bah - figured it out. This line was the issue:

  "favicon": "fabric.ico",