# FacebookUnsentMessage: reconstructing Messenger history sync

> FacebookUnsentMessage recreates the Messenger web client's MQTT-over-WebSocket history sync channel in Node.js. It authenticates with the user's browser cookies, requests replay from a sequence ID and scans message deltas for a specified message ID.

- Type: Case study
- Targets: Protocol · Website
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-06
- Added to the catalog: 2026-11-08
- Original resource: <https://github.com/khangzxrr/FacebookUnsentMessage>
- Primary source: <https://github.com/khangzxrr/FacebookUnsentMessage/blob/40d28038c268a7bc83c81347db03f1855261dbe9/README.md>
- Catalog page: <https://awesomerea.org/resources/facebook-unsent-message-case/>
- Record JSON: <https://awesomerea.org/resources/facebook-unsent-message-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/facebook-unsent-message-case/index.md)

## Requirements & limits

- **Prerequisites:** Node.js, an account owned by the user, its browser session cookies and a message ID.
- **Limits:** The author describes it as a July 2021 experiment whose undocumented Messenger behavior may have changed.
- **License:** The package.json declares an ISC license; no licence file is present.

## Primary sources

1. <https://github.com/khangzxrr/FacebookUnsentMessage/blob/40d28038c268a7bc83c81347db03f1855261dbe9/README.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.