I lost two days of research tabs to a Chrome update, so I built Tabcove: automatic, local-only tab backups

Last month Chrome restarted for an update while I had two days of research open across three windows. "Restore" brought back one window. Session Buddy had eaten my saved sessions the week before. So I built the thing I wanted and published it this week.

What Tabcove does

• Backs up every window on a timer (only when something changed) and keeps a window you close so you can bring it back.
• Save all windows as a named session with Ctrl+Shift+S, or "save and close all" to free memory.
• Restore a whole session, one window, or just the tabs you tick. Tabs open lazily, so 200 tabs come back in seconds without eating RAM.
• Search across every saved session and backup.
• Keeps pinned tabs and tab groups.
• No account, no sync server, no analytics. Everything stays in the browser. Export to a file any time; imports OneTab and Session Buddy exports.

Free version keeps 24 hours of backups and 5 saved sessions. Pro is a one-time payment, no subscription.

The hard part: Manifest V3 service workers

MV3 kills the background service worker after about 30 seconds of inactivity, so "back up every 30 minutes" cannot be a setInterval. Tabcove uses chrome.alarms for the timer and chrome.storage.session for in-memory state, and every backup is written as a complete snapshot rather than a diff, so a worker dying mid-write never leaves a half-saved session. Restores are done in batches of windows with tabs created as discarded, which is what keeps 200-tab restores fast.

Stack: Preact + Vite + TypeScript, zero runtime dependencies, about 30 KB zipped.

Links

• Chrome Web Store: https://chromewebstore.google.com/detail/tabcove-save-restore-back/ccmjgbajjpimmhdnacanbbhmfjecjnlp
• Edge Add-ons: https://microsoftedge.microsoft.com/addons/detail/dhjlfjgodmjdbnnpaebngfdiplpdegph
• Source: https://github.com/Mern-Umair/tabcove

What is missing for you? I am shipping fixes weekly and would rather build what people actually ask for.