Mirador Viewer

TypeError: Failed to fetch

{
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    "error": "TypeError: Failed to fetch",
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    "loadedManifest": "https://api.digitale-sammlungen.de/iiif/presentation/v2/bsb10503871_00521_u001/manifest",
    "shiftBookView": false,
    "switchCanvasOnSearch": true,
    "view": "book"
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}