Privacy Policy — Preelock

Last updated: November 12, 2026

Preelock is a local-first focus and productivity tool developed by Prashant Dwivedi. This Privacy Policy applies to both the Preelock Chrome Extension (v0.5.4) and the optional Preelock Desktop Application (macOS and Windows). Preelock has no user accounts, no developer cloud backend, no analytics SDKs, and no advertising trackers.

1. Preelock Chrome Extension — Data Handled Locally

The Preelock browser extension processes browsing-related signals locally inside your browser to provide website blocking, search-keyword filtering, YouTube distraction controls, and optional pairing with Preelock Desktop on the same computer:

• Browser URLs and hostnames: Navigation and open-tab URLs are checked locally in memory against your enabled standalone Website Controls (bundled adult-domain list and distracting-domain list) and active desktop focus-session rules via Chromium declarativeNetRequest and tab listeners. When a page is blocked, the tab redirects to the extension's local blocked screen with display-only parameters (hostname and block reason/timer); blocked URLs are not uploaded.
• Search queries (in-memory only): When keyword distraction rules are active during a desktop focus session, the extension inspects the search query parameter on Google, Bing, DuckDuckGo, and YouTube search result pages strictly in memory to check for a keyword match. Search queries and full search URLs are never saved to storage or transmitted.
• YouTube page DOM, channels, playback & Watch Later: On youtube.com, content scripts read channel identifiers (UC... IDs, @handle links, metadata tags, and player response data), Watch Later playlist links (list=WL), and <video> playback state (play/pause/ended status, playhead advancement, duration, ad indicator, and tab visibility) locally to enforce channel rules, Watch Later exceptions, lecture-playback detection, and your YouTube UI hiding and autoplay controls.
• Browser identity: The extension checks browser user agent and brand signals locally so Preelock Desktop can verify a supported Chromium browser during pairing.

Local Browser Storage

The extension uses Chromium's local and session storage (chrome.storage.local and chrome.storage.session), never Chrome Sync (chrome.storage.sync):

• Persistent local settings (chrome.storage.local): Your 64-character local desktop pairing token and disabled state, a locally generated random profile UUID (client), detected browser identifier, Website Controls toggles, YouTube Controls preferences, and a bounded local cache (up to 800 entries) mapping YouTube channel IDs to @handle aliases.
• Session-only state (chrome.storage.session): Short-lived desktop focus policy leases (expiring within 70 seconds), applied policy ID, an aggregate blocked-request integer counter (on unpacked builds only, never URLs), channel-blocked tab IDs, and local connection status messages. Cleared when the browser closes.
• YouTube Watch Later session list (sessionStorage): During Watch-Later-only sessions, up to 500 video IDs from your rendered Watch Later playlist are held in youtube.com tab sessionStorage to verify allowed videos and are cleared when the session policy ends.

2. Local Communication & External Network Requests

• Loopback communication with Preelock Desktop (127.0.0.1:47832): If you connect the extension to Preelock Desktop on your own computer, requests travel strictly over loopback (http://127.0.0.1:47832/sync) authenticated by your local Bearer pairing token. Standard heartbeats include protocol version, local client UUID, browser ID, applied policy ID, aggregate block count, and error status. Only when you enable Screen Time tracking or consented session attention tracking in Preelock Desktop does the extension also include the active focused tab's hostname (HTTP/HTTPS only—never paths, page titles, or queries) along with boolean flags for browser focus, search-keyword distraction match, channel block status, and lecture video playback.
• YouTube oEmbed lookup (www.youtube.com/oembed): When you are on a YouTube video page during an active session policy and the page DOM or player object has not yet provided channel identification or a channel handle, the extension issues an HTTPS GET request to YouTube's own oEmbed endpoint (https://www.youtube.com/oembed) with that YouTube video URL solely to read the channel's author_url for local rule enforcement. This request is sent only to www.youtube.com (the first-party site you are already visiting), never runs on non-YouTube sites, and does not contact any Preelock or third-party server.

3. Preelock Desktop Application Features (Separate from Extension)

The optional Preelock Desktop application on macOS and Windows stores your focus sessions, tasks, preferences, local pairing token, and (when enabled) Screen Time website-hostname and application-usage totals in a local SQLite database on your device.

• Camera Presence Check (Desktop macOS only): Preelock Desktop offers an optional on-device camera presence check on macOS to detect whether you are at your desk during a focus session. Frames are processed in memory on your device and are never recorded, saved, or transmitted. The Preelock Chrome Extension never requests permission for or accesses your camera.

4. No Analytics, Tracking, or Third-Party Sharing

Preelock contains no analytics SDKs, telemetry collectors, crash reporters, remote executable code, or advertising identifiers. Apart from the optional first-party youtube.com/oembed channel lookup described above, extension data does not leave your device. The developer never receives, collects, sells, rents, or transfers your browsing data or personal information to any third party, and never uses extension data for advertising, profiling, or creditworthiness.

5. Data Retention, Clearing, and Deletion

• Chrome Extension: Toggle off standalone Website Controls or YouTube Controls, reset YouTube settings from the extension popup, clear extension site data in Chrome, or uninstall Preelock from chrome://extensions to permanently remove all stored extension settings, pairing tokens, and cached channel aliases.
• Preelock Desktop: Rotate or reset browser pairing tokens in Desktop Settings, delete individual sessions or use Settings to delete session history or block-attempt history, or remove the local Preelock (com.preelock.desktop) application-data directory on your computer.

6. Children

Preelock is a general productivity tool and does not knowingly collect personal information from anyone, including children under 13, because it operates no central user-data collection service.

7. Changes to This Policy

If this policy changes, the updated version will be published at this page with a revised "Last updated" date.

8. Contact

For privacy questions, contact Prashant Dwivedi at: prashantdwivedi2112@gmail.com