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/p16022coll624/909/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-79c66c9f-28e7-405c-88c0-afcb775d13a4",
      "cw-a65b6d31-6a92-4423-9289-9cc6ee5b7138"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-2af6f181-9199-46d7-8c86-9adc917d40da",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/909/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-a65b6d31-6a92-4423-9289-9cc6ee5b7138"
  }
}