NostrComments

Comment freely on any website — without censorship.

NostrComments adds a comment thread to every webpage, powered by the Nostr protocol. Comments live on public Nostr relays — no company owns them, no platform can delete them, and no moderator can decide the conversation is over.

That matters most where it is least welcome: on a news site that closed its comments, on a government page, on a corporate announcement, on an article in a country where disagreeing in public is expensive. The comment thread is attached to the page's URL, not hosted by the page's owner, so it stays reachable whether or not they want it to exist.

Published on the Chrome Web Store, on Firefox Add-ons. In active development since December 2025, with new releases most weeks.

Watch it work — sixty-six seconds: a thread on an article that has no comment section, the same thread appearing in a second browser under a different key, and then a paywalled paper, a company announcement, a government page and a post on X.

Read a thread without installing anything — a static page that queries the same relays from your own browser. Give it any address to see what has been said about it.

Privacy

NostrComments has no server. There is no account, no email, no telemetry, and no analytics of any kind — the developer never receives your data, because there is nowhere for it to go.

Because the extension can run on every page you visit, that claim deserves proof rather than trust. The short version:

• Nothing is transmitted until you explicitly enable it. On first use you get a disclosure screen; no relay is contacted before you accept it, and you can disable NostrComments per site at any time.
• Your private key never leaves your device. It is used only to sign events, and can optionally be encrypted at rest with a password (PBKDF2 + AES-GCM).
• Only what you choose to publish is published: your comment or vote and your public key — sent to the public relays you have configured, not to us.
• But the relays do see which pages you read. Finding a thread means asking them about a page, so the relays you choose learn the URL and your IP address. That is inherent to a comment system attached to URLs rather than a choice made for you, and since v22.53 it applies only to pages you actually read — never to a tab you did not look at or a page you left in a second. The relay list is yours: remove any you do not trust, or run your own.

The full policy is in PRIVACY.md.

Features

• Works on any website — news, blogs, paywalled content, anything
• No account required — generate a keypair in one click, or connect an existing Nostr wallet
• Truly decentralised — comments are stored on public relays, not our servers
• Profile avatars — fetches Nostr profile pictures and display names
• Dark mode — toggle between dark and light mode, or follow system preference
• Upvote / downvote — community-driven auto-hide for low-quality comments
• Delete your own comment — publishes a NIP-09 request; relays that honour it drop it
• Mute users — hide comments from specific users permanently
• Mute words — hide any comment containing a word or phrase you choose
• "New" badges — comments posted since your last visit to a page are marked
• Reply notifications — get notified when someone replies to your comment
• Zaps — tip a commenter over Lightning (NIP-57)
• Portable identity — copy your key as nsec / npub (NIP-19) for any other Nostr app
• Resilient connections — relays reconnect automatically with a capped backoff
• Relative timestamps — shows "2h ago", "3d ago", etc.
• Inline media — images and videos embedded directly in comments
• Copy note link — share a direct nostr: link to any comment
• Custom relays — add or remove relays from the Settings panel
• Search and sort — newest, oldest, most upvoted
• Paginated — loads 20 comments at a time
• Share a comment to your feed — publishes it as an ordinary note with a link back, so people who do not have this extension can still see what you wrote. Behind a confirm, and never automatic
• Your threads — Settings lists the pages you have commented on, because a comment is filed under one address and there was otherwise no way back to it
• Repeated comments folded — three or more near-identical comments from one key become one line with the rest a click away. Presentation only; nothing is blocked and nothing is hidden
• Pictures can wait — turn off Load pictures automatically and every picture and avatar waits behind the name of the host it would come from until you ask for it
• The thread's address — when it differs from your address bar, because an anchor or a campaign parameter was dropped, the panel says which address the conversation is filed under

Installation

Chrome / Brave / Edge

Install from the Chrome Web Store.

Or load it manually, without the store:

1. Download NostrComments-Chrome-vX.Y.zip from the latest release and unzip it
2. Go to chrome://extensions → enable Developer mode
3. Click Load unpacked and select the unzipped folder

Firefox

Install from Firefox Add-ons.

Or manually: download NostrComments-Firefox-vX.Y.xpi from the latest release and drag it into Firefox, or open about:addons → gear icon → Install Add-on From File.

Userscript (no longer updated)

The userscript is frozen at 23.2.0. It still works, but it gets no new features and no fixes. A userscript has no background context, so it cannot open relay connections outside the page, and on sites with a strict Content-Security-Policy (x.com among them) Firefox refuses them. Install the extension instead. Details in NostrComments-Userscript/README.md.

Getting started

When you open the comment panel for the first time you will see a disclosure screen explaining what gets sent where. After you accept it, the onboarding screen offers two options:

1. Generate a key — click Start commenting — generate your key. A keypair is created locally in your browser. Back it up from the ⚙ Settings panel — you can copy it as nsec to use the same identity in any other Nostr app — and consider setting a password to encrypt it at rest.
2. Connect a wallet — use Alby for signing via the NIP-07 browser extension standard, or a dedicated signer: nos2x on Chrome, Attest on Firefox.

Default relays

• wss://nos.lol
• wss://relay.damus.io
• wss://relay.nostr.band
• wss://relay.primal.net
• wss://relay.snort.social
• wss://offchain.pub

You can add or remove relays from the ⚙ Settings panel inside the extension.

Development

No build system, no dependencies, no package manager. The extension is a single content script per distribution, and the two distributions are kept in lockstep.

node tests/run.mjs         # run the test suite (Node 18+, no packages to install)
node tests/browser-qa.mjs  # drive the real extension in a browser (needs chromium + chromedriver)
sh build.sh                # produce the Chrome .zip and Firefox .xpi into dist/

The tests extract and exercise the real code from the shipped source files, so they fail if shipped behaviour changes. They cover the hand-rolled secp256k1 / BIP-340 Schnorr implementation (including the official BIP-340 reference vector, so events interoperate with other Nostr clients), event signature verification, at-rest key encryption, URL normalisation, NIP-19 identity encoding, the Lightning payment path, and byte-identical parity of the security-critical code across the Chrome and Firefox builds.

browser-qa.mjs is separate because it needs a browser: it loads the unpacked extension in chromium, drives the panel, and measures WCAG AA contrast against what is actually painted on screen. See tests/README.md for what each suite covers.

Contributing

Pull requests welcome. Please run node tests/run.mjs before opening one, and keep the three distributions in sync — tests/parity.test.mjs will tell you if you missed one.

Support

NostrComments is free and open source, and every feature stays that way — there is no paid tier and nothing is held back. If it is useful to you, there is a one-line Support the developer row at the bottom of the comment panel — a zap or two, and an arrow that opens the rest — sending sats straight from your wallet to mine over Lightning. No account, no server in between.

If you have no wallet open and would rather scan something, there is a payment page at https://coinos.io/slurpnc — same wallet as the Lightning address below, showing a QR code and taking any amount.

Or send to one of these directly:

• Lightning: slurpnc@coinos.io
• Nostr: npub1ewxm82gprxwkh9qznauyey6vwx62xetpsux3prnmddkyevasatgswmds9e
• On-chain Bitcoin: 198yNVWJz2H8PwmNsX72URVVV9pRbxMb18
• Monero: 87aDTPD9HQx2QenKsS7MvHDdqsziFPD7UB37X6G5XVXc2ZPhAs8DdEKUPYJijVcRjj1gU5KvxLCTfWUKWqrd1D5o8uw5EpM

License

MIT