TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://colenda.library.upenn.edu/items/ark:/81431/p3j960k8t/manifest",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
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      "cw-1b9b7e82-1025-4422-9f65-777b31899abe"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-dadb002e-3f3d-482d-af86-a4e76708628a",
    "manifestId": "https://colenda.library.upenn.edu/items/ark:/81431/p3j960k8t/manifest",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-1b9b7e82-1025-4422-9f65-777b31899abe",
    "loadedManifest": "https://colenda.library.upenn.edu/items/ark:/81431/p3j960k8t/manifest",
    "canvasIndex": 2,
    "allowMaximize": false
  }
}