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/p16022coll246/240/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-eeb325a3-46a1-4a88-97ab-ebf2f205011b",
      "cw-01a0d423-fd8b-438a-91fb-8d38e876567f"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-58e9dd0d-81ba-4bea-9ed1-7bda5035646e",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/240/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-01a0d423-fd8b-438a-91fb-8d38e876567f"
  }
}