Checkers Online is a Chrome extension with a single purpose: to let you play checkers (draughts) - Russian, English and International rules - directly from the browser toolbar popup. You can play against a bot, with a friend via an invite link or code, or find an opponent through online matchmaking.

The extension uses the same account as the website checkers.happyvials.com. It does not read, modify or track the web pages you visit, and it has no functionality unrelated to playing checkers.

This policy applies only to the Chrome extension published on the Chrome Web Store (https://chrome.google.com/webstore/detail/kofpjedebkccdeooklpnoekdlboknamg). The website has its own privacy policy at /privacy.

The extension keeps a small amount of data in chrome.storage.local, which lives only inside your Chrome profile on your device. It exists solely so the popup can resume your session and your current game. The complete list:

• Session tokens (JWT access and refresh tokens) - keep you signed in to your Checkers Online account without asking for a password every time the popup opens.
• Last guest user id - lets a guest player return to the same guest account.
• Current game snapshot - the board position of your active game so it can be restored when the popup is reopened.
• Pending offline moves - moves made while the connection was down, queued until they can be delivered to the server.
• Game settings - preferred variant (Russian, English, International), clock settings and bot strength.
• Board theme - your visual preference for the board.

Nothing is read from other websites or from your browsing history, and no data from other sites is ever written to this storage.

The extension communicates only with https://checkers.happyvials.com - the same backend as the website - over HTTPS: a REST API under /api/* (authentication, profile, games) and a Socket.IO connection for realtime game state. The data exchanged is limited to what is needed to run your games:

• Starting as a guest - nothing personal is sent; the server issues an anonymous guest account and a session token.
• Registering, signing in or linking a guest to an account - your email address, password (sent encrypted over HTTPS, stored only as a hash) and nickname.
• During games - your moves, game state, clock information, game results (win/loss/draw) and invite codes when you play with a friend.
• Profile data read back from the server - nickname, rating (Elo), coins, wins/losses and similar game statistics.
• Technical data inherent to any HTTPS connection - your IP address and request time appear in the server’s technical logs for security and reliability only; they are not used for advertising or profiling.

The extension does not collect or transmit your browsing history, the content of other tabs, bookmarks, cookies from other sites, your location, or any other information unrelated to playing checkers.

The extension requests the minimum set of Chrome permissions required for its single purpose:

• storage - saves the items listed above (session tokens, guest id, current game, queued moves, settings and board theme) in chrome.storage.local on your device.
• alarms - Chrome suspends extension service workers when idle. A short periodic alarm (about every 24 seconds) keeps the realtime Socket.IO connection to checkers.happyvials.com alive during a game, and a one-minute alarm retries delivery of moves queued while offline. Alarms are used for nothing else.
• Host permission for https://checkers.happyvials.com/* - lets the extension call our own API and open the realtime game connection. The extension can reach this single host only and has no access to any other website.
• externally_connectable (https://checkers.happyvials.com/*) - lets the website send a SET_SESSION or CLEAR_SESSION message to the extension so that signing in or out on the website also signs you in or out in the extension. Nothing else is exchanged, and no other website can message the extension.

The extension has no content scripts and does not request tabs, history, cookies, webRequest or “all sites” access. On install or update it opens checkers.happyvials.com in a new tab once, and the uninstall link points to the same website.

All JavaScript that runs in the extension is bundled inside the package reviewed by the Chrome Web Store. The extension does not download or execute remote scripts, does not evaluate code received over the network and does not load code from external servers. Only data (JSON game state and account responses) is exchanged with our server.

The extension itself contains no analytics, advertising, tracking or crash-reporting SDKs and makes no requests to any third party. The only network endpoint it contacts is https://checkers.happyvials.com.

The website checkers.happyvials.com, which the extension opens after installation, uses Google Analytics 4 to measure page visits. That applies only to website pages loaded in a browser tab and is described in the site privacy policy at /privacy. No analytics run inside the extension popup or its service worker.

We do not sell, rent or share your personal data, session tokens or game history with third parties. We may disclose data only where required by law.

Our use of information received from Chrome APIs adheres to the Chrome Web Store User Data Policy, including the Limited Use requirements. Specifically, we certify that user data handled by this extension is:

• Not sold or transferred to third parties, other than as needed to provide the game to you (our own server).
• Not used or transferred for purposes unrelated to the extension’s single purpose - playing checkers with your Checkers Online account.
• Not used or transferred to determine creditworthiness or for lending purposes.

You stay in control of your data at all times:

• Sign out in the extension - removes the session tokens and the current game snapshot from chrome.storage.local immediately. Session tokens also expire automatically.
• Remove the extension - Chrome deletes all of the extension’s chrome.storage data on uninstall.
• Server-side account data (email, nickname, statistics, game history) is kept for as long as your account exists. Guest accounts contain no personal information.
• Account deletion - there is currently no self-service “delete account” button. To delete your account and its history, email [email protected] from the address linked to your account; we process such requests manually, normally within 30 days.

The extension is a general-audience game and is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal data, contact [email protected] and we will delete it.

We may update this policy when the extension changes - for example if a permission is added or removed. The “Last updated” date at the top of this page identifies the current version, and material changes will also be reflected in the Chrome Web Store listing. Continued use of the extension after an update means you accept the revised policy.