#370 Opt-in recovery of unsent messages, stored encrypted and local

[Anonymous]

Originally created by: kristofferR

Problem

When someone unsends a message, it disappears. The browser extension binhake/fb-unsend-viewer (72 stars, the strongest demand signal for any add-on in the November 2026 competitor review) keeps a local copy and shows unsent messages, images and voice clips again.

Design constraints

• Opt-in, off by default, with a clear explanation in Settings of what is stored and that it may conflict with the other person's expectations.
• Store only what arrives while Chatpane is running, locally, encrypted at rest (key in the OS keychain/credential store), with a retention limit (for example 7 or 30 days) and a "Delete stored messages" button.
• Source the data from Messenger's database or the message stream, not by screenshotting the DOM.
• Show a recovered message inline where the "unsent a message" placeholder appears, clearly marked as recovered.
• Never upload or sync anything.

Testing

Unsend text, image, voice clip and reaction in 1:1 and group chats, including encrypted chats; retention purges old entries; turning the feature off deletes the store.

Part of [#349].