nodebb-plugin-chat-read-receipts

Adds WhatsApp-style read receipts and an unread messages divider to NodeBB chat.

Features

Read receipts

A small indicator is shown next to each of your own outgoing messages (never on other people's messages — same as WhatsApp).

One-on-one rooms:

• ✓ (grey) — Sent, not read yet.
• ✓✓ (blue) — Read by the other person.

Group rooms — based on each participant's last-seen time:

• ✓ (grey) — nobody else has read it yet.
• 👁 Read by k/N — read by some participants. Hover to see names.
• ✓✓ Read by all (blue) — every other participant has read it.

Receipts update live as participants read messages, and also render correctly for messages loaded lazily when scrolling up.

Unread messages divider

When you open a chat that has unread messages, a dashed "New messages" divider bar is inserted before the first unread message and the view scrolls to it automatically (with a small amount of context shown above).

• Works in both popup (minimized) chat windows and the full-page /user/:uid/chats/ view, including sidebar room switching.
• The divider disappears once you close and reopen the chat after reading.
• If a new message arrives while the chat is open but you are on a different tab/window, the divider repositions to that message.
• If all unread messages are above the initially-loaded batch, the plugin loads older messages until it finds the boundary (up to 50 batches).

How it works

• When you open a chat, the plugin fetches the per-participant read state (plugins.chatReadReceipts.getRoomReadState) before recording your visit, so the pre-visit "last seen" timestamp is used to locate the first unread message.
• After rendering the divider, your client sends the timestamp of the last loaded message to the server (plugins.chatReadReceipts.markSeen). The server broadcasts the update so other participants' receipts refresh live.
• The markSeen call uses the timestamp of the last message in the DOM — not Date.now() — so messages that arrive after the snapshot are not accidentally marked as read.

Privacy note

Read receipts are symmetric: if you can see whether others read your messages, they can see whether you read theirs.