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/p16022coll206/274/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-957dc015-a2ef-4ca0-95b2-291fd35af821",
      "cw-3c450350-db9d-4c63-8983-1a4ddf3c4633"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-73542fca-4492-48a1-8a35-859671156eb6",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll206/274/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-3c450350-db9d-4c63-8983-1a4ddf3c4633"
  }
}