Privacy Policy – TCG Clerk (Chrome Extension)

Overview

TCG Clerk helps you integrate Cardmarket pages with a backend service for inventory management and related workflows. This policy explains what the extension accesses, what it sends, and what it stores.

Data the extension accesses on Cardmarket

When you open supported Cardmarket pages, the extension may read page content needed for its features, including:

• Card/product identifiers (e.g., Cardmarket product ID) and page URL
• Card metadata shown on the page (e.g., name, expansion/set, species, language, available languages, image URL)
• Offer/inventory details shown on offers pages (e.g., offer price, quantity, condition, language, edition/reverse-holo flags)
• Sales workflow data shown on sales pages (e.g., order ID/external ID, sale stage, and item rows containing product IDs and item prices)

Data sent to the backend

The extension sends collected data to the backend you configure in the extension:

• Local mode: http://localhost:3000
• Deployed mode: https://api.tcgclerk.com

Data is transmitted to support core functionality such as card information updates, inventory sync, and sales status syncing.

Authentication

If you log in via the extension popup:

• The extension sends the username/email and password you enter to your configured backend login endpoint.
• The extension does not store your password.
• The backend returns access/refresh tokens; the extension stores these tokens locally in Chrome storage to authenticate future requests.
• The extension may also store the user identifier returned by the backend (e.g., username/email) to display your login status.

Local storage

The extension stores:

• Backend selection/settings (in Chrome sync storage)
• Authentication tokens (in Chrome local storage, until you log out or uninstall)

Data sharing / selling

• The extension does not sell your data.
• The extension does not share your data with third parties, except transmitting it to your configured backend service.

Advertising and analytics

The extension does not use third-party analytics SDKs and does not use your data for advertising or marketing.

Retention & deletion

• You can log out to clear stored authentication tokens.
• Uninstalling the extension removes its locally stored data from your browser.
• Data stored on the backend is governed by the backend operator’s retention policies.

Security

When using the deployed backend, requests are made over HTTPS. Local mode uses HTTP to localhost (your own machine).

Contact

Support (Discord): https://discord.gg/v9n2aPqjsV