The densest problem in the product: four platforms, comments distinguished from DMs, story replies as ordinary conversations, buying intent flagged, and the customer strip beside the thread. Comments carry a left rule and an explicit label — never colour alone. Note: the filter and period pills and the buying-intent buttons here sit below the 44px target floor stated in EXPERIENCE.md. They clear WCAG 2.2's 24×24 minimum, but the spine wins — build them at 44px.