KeepTogetherNode

Wrapper that forbids the page-break machinery from splitting child: under the Slice strategy the wrapped content behaves like MoveToNextPage — it moves to a fresh page whole instead of being cut at an arbitrary line. The CSS equivalent is break-inside: avoid.

Content taller than a full page still overflows past the bottom margin (there is nowhere whole to move it); keep kept-together groups smaller than one page.