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/p16022coll231/61/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-f9f41cb8-4682-4c13-b3e3-bf7e5e8eae8c",
      "cw-dba5b2e9-fadd-4209-bde6-2a47655f5d25"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-c48e3bd5-d2be-4ee5-9c85-0e23c6759d85",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll231/61/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-dba5b2e9-fadd-4209-bde6-2a47655f5d25"
  }
}