Privacy Policy — Dommedia Sign-in Guard for Gemini (browser extension)

Last updated: 31 July 2026

Dommedia Sign-in Guard for Gemini is a browser extension published by Dommedia Tech Ltd. It has one purpose: to prevent Google Gemini from being used without an authenticated Google session.

This policy covers the browser extension only, not other Dommedia products or the dommedia.tech website.

It has no backend

The extension sends no data to Dommedia or to any third party. There is no account, no analytics, no telemetry, no advertising and no tracking of any kind. Everything it does happens inside your browser.

What it reads

To decide whether you are signed in, the extension reads Google session cookies for the google.com domain — specifically whether __Secure-1PSID is present and non-empty, together with at least one of SAPISID, __Secure-3PAPISID, APISID, SID, HSID or SSID. Only their presence is used; the values are never stored, logged or transmitted. The extension reads no cookies for any other site.

What it stores

A single flag recording that a session once existed, used only to word the message on the blocked page, plus diagnostic information about its own rules. Both are held in session storage, which is local to your browser and cleared when the browser closes. Nothing is written to disk or synchronised across devices.

What it observes

The extension is notified of top-level page navigations so it can re-check the session when you open Gemini. Navigations to sites other than Gemini are ignored and never recorded. It does not read page content on any site.

What it sends

Requests you make to Gemini carry an identifying product token — the header X-GeminiAuthOnly and the same token appended to your browser's User-Agent — so that an organisation's proxy or security tooling can recognise traffic from a managed browser. The token contains no personal data and identifies the extension, not you. It is added only to requests to Gemini.

Data sharing

None. No personal data is collected, sold, or transferred, and none is used for any purpose other than deciding whether Gemini may be opened. It is not used to determine creditworthiness or for lending purposes.

Remote code

The extension executes no remotely hosted code. All logic ships in the package.

Your choices

Because no data leaves your device and nothing is retained past the browser session, there is no data for us to access, export or erase. Removing the extension removes everything it stored. Where the extension is force-installed by an employer's policy, removal is controlled by that organisation.

Changes to this policy

If the extension's behaviour changes in a way that affects anything described here, this policy will be updated in the same release, and the date at the top of this page will change. The current version is always at this address.

Contact

info@dommedia.tech — questions about this policy are answered within 30 days.

Dommedia Sign-in Guard for Gemini is not affiliated with, endorsed by, or sponsored by Google. Gemini is a trademark of Google LLC.