Mirador viewer

TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://sandbox.zenodo.org/api/iiif/record:193536/manifest",
    "isFetching": false
  },
  "viewer": null,
  "window": {
    "canvasId": "https://sandbox.zenodo.org/api/iiif/record:193536/canvas/sezame.PNG",
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-841d4416-8a50-45a9-82cb-f48517f07f15",
      "cw-ff00c0f6-df81-42fd-b6a8-a583844a29b3"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": true,
    "id": "window-b41a2630-39d8-4f8f-84f4-e7e4714fd469",
    "manifestId": "https://sandbox.zenodo.org/api/iiif/record:193536/manifest",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-ff00c0f6-df81-42fd-b6a8-a583844a29b3",
    "thumbnailNavigationPosition": "far-right",
    "visibleCanvases": []
  }
}