Mirador viewer

TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://digital.libraries.psu.edu/iiif/info/maps1/28763/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-99d7f840-4715-44b7-8d1e-9b896dc052ce",
      "cw-0827aff1-3dda-444d-9388-c0b8c919c0ed"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-eca878f0-d9af-4ad7-93b2-2a2892ea5241",
    "manifestId": "https://digital.libraries.psu.edu/iiif/info/maps1/28763/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-0827aff1-3dda-444d-9388-c0b8c919c0ed"
  }
}