CHINESE SHADOWING STUDIO

Privacy Policy

Last updated 18 October 2026

This policy covers the Chinese Shadowing Studio web app (the “app”) and the companion Chrome extension “Chinese Shadowing Studio — Caption Importer” (the “extension”).

The short version

Nothing leaves your device except the requests you explicitly trigger: translation calls to the provider whose key you entered, and YouTube playback. There is no account, no analytics, no tracking, and no server that stores your data or sees your captions.

What the extension accesses

• The active YouTube tab, only when you press its Study on Chinese Studio button: the caption track list from the player and the caption file for the track you chose. This is the same data the YouTube player already downloads to show subtitles.
• That caption data is handed to the app (which opens in a new tab) through Chrome's own extension messaging, where it is stored in your browser's IndexedDB as a lesson.

The extension does not read any other page or tab, does not collect browsing history, does not run on the app or YouTube in the background, does not contact any server of ours (there is none), and does not store anything by itself — its two in-memory lookup maps are discarded when the service worker stops.

What the app stores

Lessons, segments, saved vocabulary, settings, and API keys live only in your browser (IndexedDB and localStorage). API keys are sent only to the translation provider you selected, as part of the request you asked for. Backups are files you download yourself.

Translation providers

When you translate, the app calls the provider you configured (Gemini, Groq, OpenRouter, DeepSeek, or a custom OpenAI-compatible endpoint) directly from your browser, with your key. Their handling of that request is covered by their own privacy policy. No key is ever sent anywhere else.

Permissions the extension requests

• Host access to youtube.com — to read the captions you asked to import.
• Host access to the studio's own origins — to hand the captions to the app page.
• No API permissions are requested (for example, no tabs, storage, or history).

Children, analytics, and selling data

The app and extension are suitable for general audiences, collect no analytics or telemetry, and no data is ever sold or shared with third parties by us — because none reaches us.

Changes

Material changes to this policy will be published here with the date above updated, and committed to the project's source tree.

Contact

Questions or problems: son.ngoc@protonmail.com.