HTML Email Attachment Preview does not collect, transmit, or share any personal data. Everything the extension does happens locally in your browser.

What data is stored

The extension stores only two things, and only inside your browser:

1. Trusted-senders allowlist — a list of email addresses you explicitly marked as trusted via the "Always trust this sender" banner. Stored in browser.storage.sync, which the browser synchronizes across your own signed-in browsers. This data never reaches any server operated by the extension developer.
2. Auto-allow preference — a single boolean (on/off) for the popup toggle. Same storage as above.

You can remove either at any time from the extension popup.

What data is NOT collected

• No email bodies, no email metadata, no recipient information.
• No HTML attachment contents.
• No browsing history, no page contents.
• No analytics, no telemetry, no tracking pixels, no third-party SDKs.
• No remote server operated by the extension.

Network activity

The extension performs network requests only for attachment downloads that the user's mail service (Gmail, Naver Mail, Daum Mail, Kakao Mail) already exposes to the signed-in session. These requests go from the user's browser to the mail service using the user's own authentication cookies — the extension does not proxy, log, or forward them.

Rendered attachments are shown inside a sandboxed extension page at an opaque origin. The extension does not send the rendered HTML anywhere.

Permissions

• storage — save the trusted-senders allowlist and the auto-allow preference.
• Host permissions (mail.google.com, mail.naver.com, mail.daum.net, mail.kakao.com, and their attachment-download subdomains) — detect HTML attachments in the mail UI and fetch the attachment payload for rendering.

Data deletion

• Remove individual trusted senders via the popup.
• Uninstall the extension to remove all stored data.

Contact

• Developer: Jeongseop Park
• Email: parkjeongseop@parkjeongseop.com

Full policy (English + 한국어): https://github.com/ParkJeongseop/HTML-Email-Attachment-Preview/blob/main/docs/PRIVACY.md