What exactly does "Replace" change in my book, and what does it leave alone?

From version 1.9.23, "Replace" on the book's page changes the word in the chapters, the front and back matter, the outline, the Codex (characters, relationships, secrets, places and the Mystery board), the Codex notes and interview stories, the book plan, the book's title, subtitle and topic, the chapter titles and instructions, and the chapter summaries the AI uses to remember the book. It never changes the addresses of pictures and links (their visible words do change), character name variables such as {{f:tom}}, web addresses, or the internal keys of the Codex. In a series, the series' shared Codex is not changed, because it belongs to every volume. Each chapter's old text goes to its Versions panel first.