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-801e52d0-451d-409c-ad3e-1520f1f17397",
      "cw-ec1f325b-5446-4262-b7b4-39cbec8734a2"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-52b1559d-e46c-49e9-b189-0743ac3305d7",
    "manifestId": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": true,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-ec1f325b-5446-4262-b7b4-39cbec8734a2",
    "loadedManifest": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "canvasIndex": 15
  }
}