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Preview of ciphertext

ciphertext by RetiredRoca

End-to-end encryption for your web chats. Messages are encrypted locally, so the site only ever sees ciphertext. Optional any-site mode.

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About this extension
ciphertext adds an independent layer of end-to-end encryption to the web chat and messaging sites you already use. The site stores and transmits only ciphertext — your plaintext never leaves your browser.

A small lock button appears on the message box. Click it, choose a recipient, type, and send. ciphertext encrypts locally and injects the ciphertext into the normal input box. Messages from your contacts are decrypted inline.

Features
• 1:1 and group messages
• ECDH P-256 + AES-256-GCM, with hybrid post-quantum encryption (ML-KEM-768)
• Add contacts by public key, GPG/OpenPGP armor, or a one-click share link
• Decrypts messages inline; unknown senders show a click-to-decrypt overlay
• Encrypted, passphrase-protected backups (.ccbackup)
• No accounts, no servers, no tracking — keys are stored locally and never leave your device

Back up before updating: export a .ccbackup (My Keys → Export backup) before installing a new version. Your identity and contacts live only in your browser, and a new version may change the message format.

Compatibility: newer versions read messages from older releases; older clients must update to read new-format messages.

Open source under AGPL-3.0.

ciphertext is alpha software and has not been independently audited. Do not rely on it where your safety or legal exposure depends on it.
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Permissions and data

Required permissions:

  • Input data to the clipboard
  • Access your data for sites in the slack.com domain
  • Access your data for discord.com
  • Access your data for web.whatsapp.com
  • Access your data for web.telegram.org
  • Access your data for www.instagram.com
  • Access your data for x.com
  • Access your data for twitter.com
  • Access your data for www.facebook.com
  • Access your data for www.messenger.com
  • Access your data for retiredroca.github.io

Optional permissions:

  • Access your data for sites in the slack.com domain
  • Access your data for discord.com
  • Access your data for web.whatsapp.com
  • Access your data for web.telegram.org
  • Access your data for www.instagram.com
  • Access your data for x.com
  • Access your data for twitter.com
  • Access your data for www.facebook.com
  • Access your data for www.messenger.com
  • Access your data for retiredroca.github.io

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
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Version
0.9.2
Size
77.15 kB
Last updated
6 days ago (19 Sep 2026)
Related Categories
  • Privacy & Security
Licence
GNU Affero General Public Licence v3.0 only
Privacy Policy
Read the privacy policy for this add-on
Version History
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