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-63bfb194-9d01-472a-be63-102f451c5048",
      "cw-f1ed2272-9813-458b-aed2-fef0bd4ad9ed"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-c4bdbace-5d14-41e6-8765-ac7d03c75a05",
    "manifestId": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": true,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-f1ed2272-9813-458b-aed2-fef0bd4ad9ed",
    "loadedManifest": "https://www.rammses.it/wp-content/manifestoso.json?type=sbn",
    "canvasIndex": 15
  }
}