Mirador viewer

TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-ade979fa-649e-44e5-bf86-64e4b07b6cbf",
      "cw-dfbae94d-0d54-4ba9-8a73-21e5e52b8348"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-d6b9f2b9-2324-4dee-9f4e-3f909e4b92fd",
    "manifestId": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": true,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-dfbae94d-0d54-4ba9-8a73-21e5e52b8348",
    "loadedManifest": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "canvasIndex": 15
  }
}