Comments, history & assigning people — Comment on any record

Every row carries a speech-bubble at its right-hand end. It shows a number when the record has discussion, and turns accent-coloured when someone has @mentioned you there and you haven't read it yet — so you can see at a glance which rows are talking, and which are talking to you. Click it and the record opens straight on its Comments tab. You can also open a record any other way — click the row, press Space, or open the full record page — and pick Comments. The box at the top takes a comment; Ctrl+Enter posts it. Type @ to mention a teammate — pick them from the list and they're notified in their bell, and by email too if their notification settings say so (Settings → Notifications, Mentions). The same thread appears in the peek drawer, on the full record page and in the table panel; it is one conversation wherever you open it.