What does the "Who the reader suspects" chart show?

From version 1.9.22, the Mystery board (in the Codex) draws one line per suspect: how suspicious they look to the reader, chapter after chapter, based on the clues and red herrings placed so far. A good mystery keeps several lines close and hides the culprit in the pack until the reveal. If the culprit's line rises far above the others early, the reader will guess. Click a chapter on the chart to light up its clues in the list below; a clue you add then goes into that chapter.