Bookmarks are a mark, not a point: both formats store a range, and only a
range lets a REF recompute its text. A cross-reference caches its display
like a Word field and resolves live on each pagination settle — the
bookmark's text, or the page it renders on — keeping the cached value when
the target is gone. Ctrl+click jumps to it, internal #name links too.
ODF splices its sentinels into the run text so cells and custom paragraphs
need no separate emitter; DOCX needs no post-pass at all.
Steffen Becker