Subtitle Overlay is a Chrome extension that lets you overlay subtitles on any video playing in your browser. We take privacy seriously and follow the principle of collecting only what is strictly necessary to make the extension work.
Data stored on your device
The extension uses chrome.storage.local (Chrome's per-extension local storage) to remember:
- Your settings — appearance, position, keyboard preferences, toggles.
- Downloaded subtitles — subtitle files you have downloaded through the built-in OpenSubtitles search.
- Auto-restore cache — for each video you load subtitles on, we store the subtitle content and your sync offset so the extension can restore them the next time you visit the same video. The cache is keyed by a SHA-256 hash of the page origin + path + rounded video duration; the original URL is not stored. The cache is capped at 5 MB and oldest entries are evicted automatically.
All of the above stays on your device. None of it is transmitted anywhere unless you explicitly perform an action that requires a network request (see below).
Data sent to external services
1. OpenSubtitles.com — only when you search
When you type a query in the Subtitles tab and press search, the extension sends your search text and your OpenSubtitles API key (if configured) to api.opensubtitles.com so it can return matching subtitles. See OpenSubtitles' own privacy policy for how they handle that request.
2. Anonymous usage analytics — opt-out via Settings
If you leave the "Share anonymous usage data" toggle enabled (Settings → General), the extension sends anonymous product analytics to PostHog (US/EU region). This is used to understand which features matter to users and prioritize future work. We send:
- Hashed URL (SHA-256 of the page URL) — lets us see whether a user returns to the same site without revealing which site or which video.
- Feature events — e.g. "subtitle loaded", "sync adjusted", "auto-restore accepted", "side panel opened". No content, no input text.
- Anonymous installation ID generated locally; not tied to any account.
You can disable analytics at any time in Settings — once disabled, no analytics requests are made.
What we never collect
- The text content of any subtitle file — neither files you upload nor files you download.
- Raw URLs of pages you visit. URLs are SHA-256 hashed before they leave your device, and the unhashed URL is never logged or transmitted.
- Video content, audio, screenshots, or anything from the page DOM other than the active video's duration.
- Personal information such as name, email, address, payment info, or account identifiers.
- Browsing history outside of subtitles you actively load.
Permissions
activeTab,scripting— to inject the subtitle overlay into the page you're actively viewing.storage— for the local data described above.host_permissionsforapi.opensubtitles.com(subtitle search) andus.i.posthog.com/eu.i.posthog.com(analytics, if enabled).
Your controls
- Disable analytics: Settings → General → toggle off "Share anonymous usage data".
- Disable auto-restore: Settings → General → toggle off "Auto-restore subtitles".
- Clear all stored data: Visit
chrome://extensions, find Subtitle Overlay, click "Details" → "Extension options" or remove and reinstall the extension.
Children
Subtitle Overlay is not directed at children under 13 and does not knowingly collect data from them.
Changes to this policy
If we materially change what data is collected or how it is used, this document will be updated and the effective date at the top revised. The latest version always lives at this URL.
Contact
Questions or concerns? Contact the maintainer through the Chrome Web Store listing's support tab.