Write WordprocessingML 2003 by rewriting the DOCX writer's package into the 2003 vocabulary; file.save/saveAs take format wordml2003, File > Export lists the format, CLI convert --format wordml2003, a plain save over a 2003 file keeps it.
Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>
