Privacy Policy
Privacy Policy
Effective date: 20 August 2026. Last updated: 13 September 2026. Operator: TubeLingua (dinghongzju@gmail.com). This website is public. You do not need a Google account to read this page. No ads, no analytics.
What this app is
TubeLingua is a Chrome extension. It overlays bilingual captions on YouTube, lets you look up words on the current sentence, loop one caption, and save timestamped notes. Google sign-in happens only inside the installed extension, to sync notes and unlock captions. You can read this home page and this policy without signing in.
What we do not do
- We do not sell or share user data with advertisers
- We do not collect health or precise location data; Stripe processes cards, and card numbers never reach our servers
- We do not record your browsing history on other websites
- We do not upload your own translation API keys to TubeLingua servers (keys stay on this computer)
- We do not send caption text to the developer’s servers (captions go only to the translation engine in use)
Interface settings live in chrome.storage.sync with your Chrome profile, not on TubeLingua servers.
Google user data we access
When you sign in with Google inside the extension, we request only:
userinfo.email— your Google account emailuserinfo.profile— your Google display name and profile photo
From Google we also receive the stable user id (sub). We do not request Gmail, Drive, Contacts, Calendar, or YouTube account scopes. We do not read your Google browsing history.
- Email, name, and photo: show who is signed in in the side panel
- Google
sub: primary key for your notes and paid/trial access on our Cloudflare Worker - Email: optional Stripe Checkout
customer_emailso a receipt can be sent; also to grant lifetime access if the address is on our allowlist
How we use Google user data
We use Google user data only to provide bilingual captions access, notes sync, and paid entitlements. We do not use it for advertising, profiling, or resale. We comply with the Chrome Web Store User Data Policy, including Limited Use requirements.
How we store Google user data
Email, name, photo, and Google sub are stored on our Cloudflare Worker and D1 database so we can identify the account, sync notes, and check trial or subscription status. Note text is stored in the same place. Access tokens stay with Chrome Identity until you sign out.
How we share Google user data
- We do not sell or rent Google user data to advertisers
- Cloudflare is a processor that hosts this data on our instructions
- Stripe may receive the email at checkout so a receipt can be sent; card numbers never reach our servers
- Translation APIs receive caption text only, never the Google account, email, or photo
- We do not share Google user data with other third parties except as needed to run TubeLingua
After you delete notes or email us to delete the account, we remove the matching records from Cloudflare. Uninstalling the extension does not by itself delete cloud data.
Other data we process
1. Local settings
Target language, translation engine, caption position, fonts, and UI language stay in the browser. If Chrome Sync is on, they follow your Chrome account to your other devices, not to us.
2. Notes
Stored fields: word, gloss, sentence, translation snippet, video id/title, timestamps, target language, created time. If cloud sync is not configured, notes are unavailable.
3. Caption text (translation only)
- Full track: YouTube timedtext translation
- Smart sentence: Google public translate API
translate.googleapis.com - Auto (default): full track when possible, otherwise smart sentence
- Bring your own key (optional): captions go only to the provider you configured
The developer does not log this text.
4. Your API keys
Stored in chrome.storage.local on this computer, not synced. Used only as authorization headers for the provider you chose.
5. Payments (Stripe)
Bilingual captions and notes require a subscription. Checkout runs on Stripe. We receive “paid / renewed / trial started” webhooks to extend access. We do not store card numbers, CVC, or full billing addresses. Stripe handles payment data under its privacy policy.
Permissions
storage— settings and optional keysidentity— Google sign-in for notessidePanel— study side panel- YouTube pages — bilingual captions, lookup, sentence looping
translate.googleapis.com— smart-sentence translationoauth2.googleapis.com— revoke the token on sign-out- TubeLingua Worker — notes API
The extension does not request tabs and does not read URLs of unrelated sites.
Deletion
Delete individual notes in the extension Notes tab. Uninstalling clears local settings and API keys; cloud notes remain until you delete them while signed in, or email dinghongzju@gmail.com with the Google account to delete. Sign-out revokes the Google token.
Children
This extension is not directed at children under 13. Notes require a Google account. If you cannot agree to this policy, do not use sign-in.