The structural header, beside the styling one: pageBreaks grows the
between-rows spacer by the first row's height and draws a copy of that
row — colgroup included, so the columns line up — at the foot of the
gap, which is the top of the continuation. Round-trips as ODF
table:table-header-rows and Word's w:tblHeader; LibreOffice keeps both.
Word's "don't allow row to break" needs nothing: a row that fits a page
is already an atomic leaf here.
Steffen Becker
cb1c61c900