What was typed in this room, oldest first.

Read on joining, so someone who arrives late or reconnects sees the conversation instead of an empty panel — and so the link a teacher pasted ten minutes ago is still there.

Scoped to the ROOM, not the class: a breakout's chat belongs to that breakout. Class-wide gathering is the class report's job.

PRIVATE ROWS ARE EXCLUDED, and that exclusion is load-bearing rather than tidy. Every client fetches this on connect; without the filter, a student rejoining after a dropped connection would be handed every other student's private question to the teacher, in the ordinary chat panel, with no indication that it was ever meant to be private. The quiet lane has its own endpoint with its own gate — see get_class_private_messages.