Mirador viewer

SyntaxError: Unexpected token '<', "<!DOCTYPE "... is not valid JSON

{
  "manifest": {
    "error": "SyntaxError: Unexpected token '<', \"<!DOCTYPE \"... is not valid JSON",
    "id": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/363/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-2e517f9e-cf1c-486d-a276-31640aa71ef8",
      "cw-34518244-7655-4b9c-813f-06968516584d"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-b12130d7-eed1-49e5-b78b-9255cab0800b",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/363/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-34518244-7655-4b9c-813f-06968516584d"
  }
}