@zip.js/zip.js
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    Variable ERR_UNDEFINED_READERConst

    ERR_UNDEFINED_READER: string

    Undefined reader error

    Thrown when adding an entry with the ZipWriterConstructorOptions#passThrough option set to true and no Reader instance: the headers of such an entry describe its content verbatim and would declare content that is not there. Directory entries are exempt, they have no content to write as-is.