Mirador viewer

SyntaxError: Unexpected token 'I', "I don't kn"... is not valid JSON

{
  "manifest": {
    "error": "SyntaxError: Unexpected token 'I', \"I don't kn\"... is not valid JSON",
    "id": "https://iiif.participatory-archives.ch/SGV_12S_01038/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-9fe76e0a-0924-412a-8ccb-d18a4596a85c",
      "cw-b0c5ce3d-c390-4f9f-84bf-fee9e5151800"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-a3942555-f3c9-4ecc-ac35-a6d9757f7f33",
    "manifestId": "https://iiif.participatory-archives.ch/SGV_12S_01038/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": true,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-b0c5ce3d-c390-4f9f-84bf-fee9e5151800",
    "loadedManifest": "https://iiif.participatory-archives.ch/SGV_12S_01038/manifest.json"
  }
}