Privacy Policy

TrailMail (Chrome extension) · Last updated: 14 July 2026

TrailMail ("the extension") helps you predict likely work-email addresses from public company email patterns, request referrals from a job posting, and, optionally, send emails from your own Gmail account. This policy explains exactly what the extension does and does not do with data, including data obtained through Google APIs.

Summary

The extension has no backend server of its own. It runs entirely in your browser.
We do not sell, rent, or share your data, and we do not run analytics or advertising trackers.
Data is sent only to services you configure or authorize: Hunter.io and Google (Gmail).

How TrailMail uses Google user data

TrailMail integrates with Google only so that you can send prediction-generated emails from your own Gmail account, with your explicit, revocable authorization via Google Sign-In (OAuth). TrailMail requests exactly three scopes, each used for a single, narrow purpose:

https://www.googleapis.com/auth/gmail.send — used only to transmit the messages you compose and click "send" on, one at a time, directly to Gmail's API. This scope is send-only: TrailMail cannot read, search, list, label, delete, forward, or otherwise access any email already in your mailbox, your contacts, or your drafts.
email (Google userinfo) — used once per sign-in, purely to look up and display which Gmail address is currently connected inside the extension's popup, so you know which account will be used to send.
openid — used as part of the standard Google Sign-In handshake to authenticate the connection; no separate profile data is requested or stored.

Beyond these three narrow uses, TrailMail does not:

read, transmit, or expose the content of any Gmail message other than the one you actively send;
share, sell, rent, or transfer Google user data to any third party, advertiser, or data broker;
use Google user data for advertising, profiling, or any purpose unrelated to sending the message you initiated;
use Google user data to train, improve, or fine-tune any AI/ML model, generalized or otherwise;
allow any human (including us) to read Google user data, except where you directly contact us for support about a specific problem and voluntarily share it.

TrailMail's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

What the extension accesses

Public LinkedIn profile data (names, companies, occupations) visible on the pages you open. This is read in your browser to generate predicted emails. It is not transmitted to us or stored off your device.
Public job-posting data on supported job boards (applicant tracking systems such as Greenhouse, Lever, Ashby, Workday and similar) that you open. When you choose to request a referral, the extension reads the visible posting (company, job title, description) in your browser to identify the company and personalize your message. It is not transmitted to us or stored off your device.
Company names are sent to Hunter.io (using your own API key) to look up a company's email domain and pattern. See Hunter.io's privacy policy for how they process that request.
Gmail (optional, only if you connect it): with your explicit authorization the extension uses the gmail.send scope to send emails you compose from your own account. It sends one message per recipient on your action. The extension cannot read, search, delete, or modify your mailbox, because gmail.send grants send only access. Your email address is read once (via Google's userinfo endpoint) only to display which account is connected.

Data security & protection mechanisms

Because Gmail access is a sensitive permission, TrailMail is built to minimize what could ever be exposed, even in principle:

No backend, no server-side storage. TrailMail has no server of its own. There is no database of your Google data for us, or anyone, to breach — the extension calls Google's APIs directly from your browser.
Encryption in transit. All communication with Google's APIs (www.googleapis.com, gmail.googleapis.com, oauth2.googleapis.com) happens over HTTPS/TLS.
OAuth tokens are never handled by us. Sign-in and token storage/refresh are delegated entirely to Chrome's built-in chrome.identity API. TrailMail's code never sees, stores, or transmits your Google password, and the access token is kept in Chrome's own secure token cache, not in our extension storage.
Local, sandboxed storage only. Anything TrailMail does store (your Hunter.io key, cached predictions, templates, send-status records) lives in chrome.storage.local, which is sandboxed to the extension and inaccessible to websites, other extensions, or us.
Least-privilege scopes. TrailMail requests the minimum scopes needed (send-only, not read/modify) and never requests broader Gmail, Contacts, or Drive access.
User-controlled revocation. You can disconnect Gmail at any time from the extension popup, which revokes the OAuth token immediately, or revoke access directly at myaccount.google.com/permissions. Uninstalling the extension removes all locally stored data.

What is stored, and where

All of the following is stored locally in your browser via chrome.storage.local and never leaves your device except as described above:

Your Hunter.io API key.
Predicted email results, cached for 14 days to avoid re-spending API credits.
Email templates you create (subject, body, optional attachment).
Records of emails you send (recipient, subject, time) used to show send status.

The Gmail access token is managed by Chrome's identity system, not stored by us. You can disconnect Gmail at any time from the extension, which revokes the token.

Optional email open/click tracking

If you enable tracking, the extension adds an invisible pixel and/or rewrites links so that opens and clicks are recorded. You may use the built-in endpoint or your own self-hosted endpoint. When tracking is enabled, open/click events (an opaque token and timestamp) are recorded at that endpoint so you can see whether your emails were opened. You are responsible for disclosing tracking to recipients where the law requires it (e.g., GDPR). Tracking is off unless you turn it on.

Your responsibilities

Predicted emails are not verified and may be inaccurate. You are responsible for complying with all applicable laws when contacting people (including consent, sender identity, and unsubscribe requirements such as GDPR and CAN-SPAM).

Data deletion

Removing the extension, or clearing its storage, deletes all locally stored data. Disconnecting Gmail revokes the access token.

Contact

Questions about this policy: manan.hiren.shah@gmail.com.

← Back to TrailMail