Privacy Policy, Fluent Immigrant browser extension

Effective 9 October 2026 (previous version: 26 August 2026). Applies to the "Fluent Immigrant" extension for Chrome, Edge and Firefox. The web app at app.fluentimmigrant.com is covered by the general policy at https://fluentimmigrant.com/privacy. This policy is also published at https://app.fluentimmigrant.com/extension/privacy

WHAT CHANGED ON 9 OCTOBER 2026

The previous version said the extension does not collect which videos you watch. That was wrong for YouTube: when you save a YouTube video, or finish one with the overlay on, the extension sends that video to your account, together with YouTube's caption file for it, and it checks each YouTube video you open against your library. This version describes that, and the word counts the extension keeps for your progress. Nothing about what the extension does changed; only the description.

WHAT THE EXTENSION DOES

The extension has a single purpose: it makes the subtitles of videos on youtube.com, netflix.com and Prime Video (primevideo.com, and amazon.com only under /gp/video) clickable, so an English learner can look up a word, hear it, and mark it as Learning / Known / Mastered in their Fluent Immigrant vocabulary, and study those videos in their Fluent Immigrant account. It runs only on those sites, inside the YouTube player embedded in app.fluentimmigrant.com, and on app.fluentimmigrant.com/extension/connect, the page that links it to your account.

DATA THE EXTENSION HANDLES

• Your account connection token. Why: to act on your behalf (save words and videos to your account). It is created when you press "Connect" in the app. Where: stored on your device (extension storage) and sent only to our API with each request. You can revoke it any time from the app (Settings, Browser extension); a revoked token stops working immediately.
• Subtitle text of the video you are watching. Why: to translate the current line into your language and to colour words by your vocabulary state. Where: for the line translation, each subtitle line is sent from your browser to Google Translate (translate.googleapis.com) with only the text and the language pair; lines Google could not translate go to our API and from there to Google Gemini. Word lookups and translated lines are cached on our servers so the same text is not processed twice, not tied to your account; that cache is deleted after 365 days. To colour the words, the words of each line are sent to our API with your token and looked up in your vocabulary.
• How often you meet your own words. Why: seeing a word you are learning in a real video counts toward your progress on that word. Where: when a word from your vocabulary appears in a subtitle line, our API adds one to how many times you have seen it. These counts are saved in your account.
• Words you click or mark. Why: to show the explanation and to save the word to your vocabulary. Where: sent to our API. The word and its state become part of your vocabulary in your account, exactly as if you had marked it in the app.
• YouTube videos you save or finish (YouTube only). Why: a video you save, or watch past 70% of its length with the overlay on, is added to your Fluent Immigrant library and counts toward your daily goal. What is sent: the YouTube video ID, its title, channel name and length. Where: our API. The video becomes part of your library and study history in your account. Separately, when you open a YouTube video, the extension asks our API whether that video is already in your library (video ID only), so it can show the right "Save" button; that check is not saved to your account. Nothing about the video is sent on Netflix or Prime Video.
• YouTube's caption file for a video (YouTube only). Why: YouTube's own caption file carries the timing of each spoken word, which lets the app's subtitles follow the speech word by word. When: when you save or finish a YouTube video as described above, when you press "Watch in app" on youtube.com, and when you play a YouTube video inside app.fluentimmigrant.com (there the extension runs inside the embedded YouTube player for this one job). What is sent: the caption file of that video and its language, with your token. Where: our API keeps one copy per video and language and uses it to time that video's subtitles for every learner who studies it. The copy records which account sent it; that link is removed when you delete your account. The caption file itself is kept with no fixed deletion date.
• Your extension settings (translation on/off, font size, etc.). Why: so the overlay behaves the way you set it. Where: stored on your device only.

WHAT THE EXTENSION DOES NOT DO

• It does not collect your browsing history or the pages you visit. On youtube.com it adds a video to your account only when you save it or finish it, as described above. On Netflix and Prime Video it sends no information about what you watch.
• It reads the caption text only on a video page you already opened, and only while the overlay is enabled (inside the app's own YouTube player, only to get the caption file). On some sites it turns the player's captions on and selects the English track for you, so the overlay has text to work with.
• It does not read your Netflix, YouTube or Amazon account, cookies, or credentials.
• It does not use analytics, advertising or tracking SDKs, and it does not sell or share data with data brokers.
• It does not run on any site other than the ones listed above.

WHO RECEIVES DATA

Only Fluent Immigrant's own API (reached through app.fluentimmigrant.com/api, hosted on Render) and, for the parts of a request that need them, our processors: Google Translate (sentence translation, sent directly from your browser), Google Gemini (sentence translation for lines Google Translate could not handle, and word explanations, cached and not tied to you) and OpenAI (text-to-speech audio for a word you ask to hear). They receive the text needed for that one request and nothing about your identity.

RETENTION AND DELETION

Words, word counts, and videos you save or finish live in your account until you change or delete them, or delete your account (Settings, Account), which removes them together with every extension token. Caption files are kept as described above, without the link to your account once the account is deleted. Disconnecting the extension in the app revokes its token; uninstalling the extension deletes everything it stored on your device.

PERMISSIONS, IN PLAIN WORDS

• storage: keep your settings and connection token on your device.
• scripting: start the extension's own script on a video tab that was already open before the extension was installed or updated, so you do not have to refresh it. It runs only the code shipped in the extension, never anything downloaded, and it never reloads a page.
• Access to www.youtube.com, www.netflix.com, .primevideo.com and www.amazon.com/gp/video/: read the caption text and draw the clickable overlay on the video. On YouTube, also send the videos you save or finish, and their caption files, to your account.
• Access to www.youtube.com/embed and www.youtube-nocookie.com/embed: inside the YouTube player embedded in app.fluentimmigrant.com, get the caption file of the video you are playing, as described above.
• Access to app.fluentimmigrant.com (and app.thefluentimmigrant.com, the previous address, while readers move over): link the extension to your account and talk to our API.

CHANGES

If this policy changes in a way that matters, the extension's store listing and this page will say so, with the new effective date at the top.

CONTACT

Questions or requests about your data: support@fluentimmigrant.com