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/p16022coll624/73/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-d5dbf04d-8ad3-4947-ba96-290111230804",
      "cw-cc7c6714-ee11-4d5a-b3e9-333138868f60"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-1b84cac5-92ac-46a7-85d3-afa6e33f903d",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/73/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-cc7c6714-ee11-4d5a-b3e9-333138868f60"
  }
}