Parse and render first-page headers with VML/EMF images#1
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Word header logos and OLE preview pictures are commonly EMF metafiles that browsers can't decode, so they rendered as broken `<img>` boxes. The metafile almost always wraps a single PNG/JPEG bitmap record; extract it at media-load time and use that as the display URL while keeping the original bytes for round-trip. Adds an optional `mediaResolver` parse hook for hosts that want to rasterize the vector-only residual server-side. Also: recurse into `w:smartTag` (its runs were silently dropped), and capture each header/footer's original XML so unedited parts re-emit byte-identically on save instead of being rebuilt from the model.
- clear HeaderFooter.verbatimXml in the React/Vue overlay save paths (useHeaderFooterEditing / usePagesPointer) so edits aren't lost on export - mediaResolver: resolve files in parallel and swallow per-file errors so one bad conversion doesn't abort the whole parse - reuse mediaToDataUrl from unzip instead of a local duplicate - metafileRaster: drop the brittle GIF extractor; scan JPEG for the last EOI so an EXIF thumbnail doesn't truncate the outer image
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Summary
Word header logos and OLE preview pictures are commonly EMF metafiles, which browsers can't decode — they rendered as a broken
<img>box. This PR extracts the PNG/JPEG bitmap that's almost always embedded inside the metafile and uses it as the display URL, so the logo just shows up. Original EMF bytes stay onMediaFile.dataso round-trip is unaffected.Approach shipped: embedded-raster extraction (not full EMF rasterization). For the residual case — a vector-only metafile with no embedded bitmap — there's a new
parseDocx(buf, { mediaResolver })hook so a host can rasterize server-side and hand back adata:/blob:URL.Also in this PR:
w:smartTagis a transparent wrapper; recurse into it instead of dropping its runs (the Treasury template lost "WASHINGTON" without this).HeaderFooter.verbatimXml), sow:object/OLE/VML the model can't fully represent round-trips byte-identically. The HF inline editor and every model-mutation site clear it on first edit.Visual verification
Treasury information-memo template, page 1:
Header close-up (after):
Tests
packages/core/src/docx/__tests__/header-vml-emf.test.ts—extractMetafileRasteron a real EMF;parseDocxpopulatesheaders, image src isdata:image/png, smartTag runs survive,mediaResolveroverrides; round-trip leavesheader1.xml/footer1.xml/image1.emfbyte-identical; default vs first+titlePg both populate.e2e/tests/header-vml-emf.spec.ts— seal<img>decodes (naturalWidth > 0) inside.layout-page-headeron page 1; body text starts below the header band; clicking body still places the caret; header renders underexternalContentmode.mainconfirmed unrelated).Notes for upstream
Needs a
bun changeset(minor — additive public API:MediaResolver,extractMetafileRaster,HeaderFooter.verbatimXml). Left for the upstream PR per the changeset workflow.