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/p16022coll624/484/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-01eae548-822e-4d49-93d0-9ca7336b62eb",
      "cw-1f327f2f-aad6-4f58-9e9f-a57223b2bd74"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-3803cb25-27ac-415f-b4ce-95e5d92b3a32",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/484/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-1f327f2f-aad6-4f58-9e9f-a57223b2bd74"
  }
}