The marker pseudo is floated into the indent instead of absolutely
positioned, so a label the indent cannot hold — a "1.1.1." outline number,
a Roman numeral — moves the first line right the way both word processors
do, rather than printing over the words it labels. Out of flow either way,
so no list line grows.
The PDF clone's injected marker follows suit, and its chain now reads the
effective numbering and walks to the outermost multilevel list: a list
numbered by a named style had none of its own and printed a bare separator.