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HTM-063Critical Ingestion Error

SVG "xlink:href" attribute value ("resource") should be equal to th...

SVG "xlink:href" attribute value ("resource") should be equal to the "href" attribute value ("resource").

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What This Error Means in Plain English

EPUBCheck detected SVG "xlink:href" attribute value ("resource") should be equal to the "href" attribute value ("resource").. Digital reading systems and bookstores require standard conformance to ensure compatibility across all reading apps.

Why Retailers & EAA Regulations Block This File

Automated book distributors (Apple Books, Amazon KDP, Kobo, and IngramSpark) run strict EPUBCheck validation on ingest and reject non-compliant files.

Technical Specification: W3C EPUBCheck rule HTM-063: SVG "xlink:href" attribute value ("resource") should be equal to the "href" attribute value ("resource").

Manual Fix Instructions (for Sigil / Calibre)

  1. Locate the file and line flagged under rule HTM-063 in your EPUB editor (Sigil or Calibre).
  2. Apply the required syntax correction matching the HTM-063 specification.
  3. Re-pack and validate with PreFlight EPUB to confirm zero residual errors.