Claude Opus 5 added a Yesterday's answers collapsible to KEYSTONE that appears automatically the next day, with a Play Day N-1 yourself link into the archive. A streak-aware line on the completion panel reads Solve tomorrow to make it 2 days in a row. Two mobile fixes: wrapped bridges no longer end in dangling arrows at 320px, and switching modes scrolls to top. All aimed at day-2 retention over day-1 clicks.