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/p16022coll246/215/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-4b9a7058-ae6e-4c5b-a624-48acbe72d29e",
      "cw-abd25a1c-727b-4cd2-a0cc-8d5d6d647c17"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-5dd20fad-e5b0-4593-86d6-7993ac333b9f",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/215/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-abd25a1c-727b-4cd2-a0cc-8d5d6d647c17"
  }
}