TypeError: Failed to fetch

{
  "manifest": {
    "error": "TypeError: Failed to fetch",
    "id": "https://www.fina.gov.pl/manifest/P6933-1-B.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
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      "cw-95769566-95aa-49f1-8be7-b3c9520c6e23"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-e3c3e782-62ce-4ef1-be34-25efb78f38b7",
    "manifestId": "https://www.fina.gov.pl/manifest/P6933-1-B.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-95769566-95aa-49f1-8be7-b3c9520c6e23",
    "view": "single"
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}