Claude Cowork gets its own browser: no extension, no shared passwords

What happened: Starting August 26, 2026, Anthropic is gradually turning on a built-in browser in Claude Cowork. Claude can now open a webpage on its own in the desktop app's side panel, read it, click a link, or fill in a form — without you installing the Claude in Chrome extension. The browser runs separately from your own: Claude can't see your bookmarks, passwords, or history unless you explicitly give it access. The feature is rolling out week by week to the Pro, Max, and Team plans in the desktop app for macOS, Windows, and Linux (still in beta); Enterprise admins can turn it on right away. Once it reaches you, it runs automatically — give Claude a task that involves a webpage, and the browser opens on its own. If you already use the Claude in Chrome extension, that stays your default; you can switch between the two under Settings → Cowork → Preferred browser.

What it means for you: Until now you either had to copy website content into the conversation by hand, or let Claude into your own browser, with all its passwords and history, via the extension. The built-in browser is a separate sandbox Claude can use without the risk of seeing things you'd rather keep private:

• Research across multiple sites — "compare the terms of five vendors and put them in a clear table for me" without manually opening and copying ten pages
• Filling in web forms — applications, orders, support requests on sites with no API at all
• Working with internal tools that have no connector — anything with only a web interface can be handed over as a normal task

How to get started:

1. Update the Claude desktop app (macOS, Windows, or Linux beta) — you need the Pro, Max, or Team plan; on Enterprise, an admin turns it on.
2. Give Claude a task in Cowork that involves a webpage — the browser opens on its own in the side panel.
3. Under Settings → Cowork → Preferred browser, choose whether Claude should use the built-in browser or the Claude in Chrome extension.
4. Optionally, you can import saved logins from Chrome, Edge, or Firefox — banking, email, and SSO sign-ins are only carried over if you explicitly choose to include them.

Watch out for: Before Claude acts on a new site for the first time, it asks for your permission — and Anthropic explicitly recommends starting on sites you already trust. Prompt injection (a malicious instruction hidden in a page's own content) remains a real risk, even though Anthropic has built in the same safeguards used for the Claude in Chrome extension. For sensitive accounts — banking, medical records, other people's personal data — Anthropic directly advises against using the browser at all. The rule "AI proposes, the human approves" applies here quite literally: don't skip approving that first action on any new site, even when it slows you down.