Browser Extension

The extension supplies the website level half of TimeLet. It runs independently of the desktop app.

{
  "manifest_version": 3,
  "background": { "service_worker": "src/background/index.ts" },
  "permissions": ["tabs", "storage", "idle", "alarms"],
  "host_permissions": ["<all_urls>"],
  "action": { "default_popup": "src/popup/index.html" }
}

An MV3 service worker is killed aggressively. Nothing durable stays in memory: the tracker restores state from chrome.storage on every wake, and the queue is persisted before it is flushed.

chrome.tabs.onActivated.addListener(async ({ tabId }) => {
  const tab = await chrome.tabs.get(tabId);
  await session.flushCurrent();
  session.start(tab.url, tab.title);
});

chrome.tabs.onUpdated.addListener((tabId, info) => {
  if (info.url) session.navigate(info.url, info.title);
});

The extension ships its own copy of the rules so it can label activity offline. The file is duplicated from the server on purpose, which means the two must change together.

If the API is unreachable, completed blocks go to a bounded local queue and are retried on the next wake with backoff, oldest first, so ordering survives.

The extension polls for a pending control command and acknowledges it after applying it. This is how pausing tracking on the dashboard stops the extension without the user touching the browser.

cd extension
npm run build
# then chrome://extensions -> Load unpacked -> dist/