Mirador viewer

TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://digital.libraries.psu.edu/iiif/info/maps1/18888/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-e7312918-b97a-4bd3-b3ed-e95a24a0c7c6",
      "cw-4a1b0d82-f7c7-4a54-ab9d-c1e5a52421e1"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-f14e42a4-3144-4bf2-a01e-7dead9d361a6",
    "manifestId": "https://digital.libraries.psu.edu/iiif/info/maps1/18888/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-4a1b0d82-f7c7-4a54-ab9d-c1e5a52421e1"
  }
}