Renders the same document with and without the border through
LibreOffice and compares every word box — pins the fo:margin carve-out
at render level, where the round trip is blind (both sides symmetric).
Anchored exactly on the paragraph top (posOffset 0), LibreOffice's wrap
layout derails and paints a neighbouring inline text box's content
outside its shape; LO itself never writes less than a twip there.
Probed by bisecting a broken box against LO's own DOCX export of the
same document. The importer rounds the sub-visible offset back to none,
so nothing accretes on the round trip.
style:writing-mode alone leaves the paragraph left-aligned in
LibreOffice; the mode+end pair is what it writes itself (probed), so
both export paths add it where the block sets no alignment of its own,
and the importer suppresses end/right against an RTL block's default —
the pair is its normal look, not direct formatting. The render-
consistency leg now compares under spacing model 'max', the one both
formats express; thresholds re-measured.
Three legs against the closed-loop blind spot the duplicate-style bug
exposed: package-lint.test.ts checks invariants the schemas cannot
express (unique style ids/names, dangling style/num/rel references,
balanced ranges, manifest completeness); lo-roundtrip gains a
soffice→fodt leg asserting the styles LibreOffice resolves (Heading
chain Arial/bold/sizes, Word defaults); lo-render-consistency.test.ts
renders the kitchen sink from both formats through LibreOffice and
compares pagination and pixels (ratchet thresholds). CI's LO job
gains poppler-utils; test:lo runs both LO files.
Steffen Becker