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Privacy Policy

LAST UPDATED — JULY 18, 2026

This Privacy Policy explains what information the Preface browser extension ("Preface," "the Extension," "we," "us," or "our") collects, how it is used, and the choices you have. It applies to the Extension and is incorporated by reference into our Terms of Use.

Information We Collect

Text you choose to highlight

When you select (highlight) text on a webpage, Preface reads that specific selection — up to 500 characters — along with the title of the page you are currently viewing. No other content on the page is read, accessed, or stored. Preface does not have access to, and does not collect, the full text or HTML of any webpage beyond what you have actively highlighted.

Locally stored data

Preface stores the following directly on your device, using your browser's local extension storage. This data is never transmitted to us:

  • Lookup history — the terms you have highlighted and the time of each lookup, so you can review recent lookups in the popup (up to the most recent 50 entries).
  • Extension settings — whether the extension is currently enabled or disabled.
  • Terms acceptance status — a flag recording whether you have agreed to our Terms of Use.

You can clear your locally stored lookup history at any time using the "Clear" button in the Preface popup. Uninstalling the extension removes all locally stored data.

Information we do not collect

Preface does not collect your name, email address, account credentials, payment or financial account information, health information, private messages, browsing history, location data, or any keystroke, click, or mouse-movement activity. Preface does not track which websites you visit; it only acts on text you actively select on whatever page you happen to be viewing at that moment.

How Information Is Used and Shared

To generate the contextual information Preface displays, the highlighted text and page title described above are sent to the following third-party services, solely for the purpose of producing your result:

RecipientWhat is sentPurpose
Anthropic (Claude API), via our backend proxy Highlighted text (up to 500 characters) and the page title To generate historical context, implications, related-reading suggestions, and (when relevant) contextual connections to other news coverage
A market data provider (Yahoo Finance), accessed via our backend proxy A financial instrument, index, or commodity symbol inferred from the highlighted text To retrieve current market prices and related figures when the highlighted text references a financial instrument or publicly traded company

These requests pass through backend servers that we operate, which relay the request to the above providers and return the result to your browser. We do not log, retain, or build user profiles from this data beyond what is transiently necessary to relay the request and generate a response. We do not sell your data, and we do not use it for advertising or share it with any party for their own independent purposes.

Optional Accounts and Synced Lookup History

You can optionally create a free Preface account on our website to view your saved lookup history across devices on the "My Lookups" page. Accounts are entirely optional: the extension works fully without one, and if you never create an account, your lookup history stays on your device as described above.

If you create an account, we collect and store the following through Supabase, our authentication and database provider:

  • Your email address and an encrypted password, used solely to sign you in.
  • The profile details you provide at signup: a username, your education or work stage (e.g., high school, college, graduate school), and the types of searches you typically make.
  • The lookups you choose to save to your account (the highlighted term, an automatically assigned topic category, and the date saved).

Saved lookups are private to your account. Database access rules ensure each signed-in user can only read and delete their own lookups; no other user can see them. We do not sell this information, use it for advertising, or share it with any party for their own purposes. You can delete individual lookups at any time from the "My Lookups" page, and you can request full deletion of your account and all associated data by contacting us at the address in the Contact section below.

Data Retention

Highlighted text and page titles sent to generate a result are processed transiently and are not retained by us after a response is returned. Locally stored history, settings, and terms-acceptance status remain on your device until you clear them or uninstall the extension. If you create an optional account, your account details and saved lookups are retained until you delete them or request account deletion.

Your Choices

  • You can disable Preface at any time using the toggle in the extension popup, which stops the highlight-detection feature from running.
  • You can clear your locally stored lookup history at any time using the "Clear" button in the popup.
  • You can uninstall the extension at any time via your browser's extension settings, which removes all locally stored data.

Children's Privacy

Preface is not directed to children under 13, and we do not knowingly collect information from children under 13.

Changes to This Policy

We may update this Privacy Policy from time to time. Material changes will be reflected by an updated "Last updated" date above. Continued use of the Extension after changes are posted constitutes your acceptance of the revised policy.

Contact

Questions about this Privacy Policy can be sent to prefaceprep@gmail.com.


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