Privacy Policy

Last updated: March 14, 2026

What Mustard does

Mustard is a browser extension that lets you annotate web pages with notes. Notes can be saved locally in your browser or published to share with your Bluesky and GitHub followers.

Data we collect

• Account information: If you log in, we receive account information from the provider you use — your Bluesky DID (decentralized identifier) or your GitHub account id — along with public profile information (display name, handle, avatar). This is used solely for authentication and displaying note authorship.
• Published notes: When you publish a note, we store the note content (up to 300 characters), the page URL it is attached to, and positioning data (CSS selector or click coordinates). This data is stored on our server (Supabase) and is visible to anyone who follows you on Bluesky or GitHub.
• Page URLs: When you visit a page, the extension checks whether any published notes exist for that URL. No other page data is read or collected.

Data stored locally

Notes saved locally are stored in your browser's extension storage and never leave your browser. Your authentication session is also stored locally.

Data we do NOT collect

• We do not collect browsing history
• We do not read or collect page content
• We do not use analytics or tracking
• We do not sell or share data with third parties

Third-party services

• Supabase: Hosts our database and server functions. Published notes and authentication tokens are processed through Supabase.
• Bluesky (AT Protocol): Used for authentication and fetching your social graph (who you follow) to determine which notes to display.
• GitHub: Used for authentication and fetching your social graph (who you follow) to determine which notes to display.

Data deletion

You can delete any note you have created at any time using the delete button on the note. Local notes are removed from your browser immediately. Published notes are removed from our server immediately. Uninstalling the extension removes all local data.

Contact

If you have questions about this privacy policy, open an issue at github.com/fettstorch/mustard.