Sub-ticket of MARS-99 Multi-tooth RX tagging UX: passive-strong signal, not nag. (a) dropdown already lists only the práctica's selected teeth [live]; (b) untagged RX card gets red border + 'elegí la pieza' placeholder as primary passive cue; (c) auto-open+flash ONLY the last-added image's dropdown (never all — batch-add of N would fire N opens); (d) submit-with-untagged scrolls to+opens first offender instead of a toast. No modal. Single-tooth keeps silent auto-pick. Brainstorm: coder-mars+audit-mars-cc, approved Elazar 2026-06-12. Build after B2 edit-path. · mars