A hidden copy follows its visible main child's layout-derived position.
Only the frontend runs real reflow, so comparing that copy's raw position
with the pure runner reported a false mismatch (F227).
Compare untouched images against expected source placement for backend
parity. Keep strict same-run comparisons and the numeric tolerances.
Independent controls still reject image drift and authored geometry edits.
The source/image translation control fails before the correction.
Reduce the generated history from 41 operations to five and replay it in
common and the async frontend, including exact undo and redo.
Validation: 30 focused tests / 177 assertions; full common JVM/JS,
frontend, backend and exporter suites; lint and formatting. All six
generated properties pass 40 programs at seed 712. Golden data and
production behavior are unchanged.
AI-assisted-by: GPT-6
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