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/p16022coll230/3691/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-f0298a1b-91d9-49f2-b4d2-e6328fc42535",
      "cw-253bfc84-c69c-4482-bd53-db2e17accca6"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-824481e2-457b-4724-a0fb-3087a3e67bb1",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/3691/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-253bfc84-c69c-4482-bd53-db2e17accca6"
  }
}