Feature request: allow Browser use to use an external/system browser profile

What variant of Codex are you using?

macOS App

What feature would you like to see?

I would like Codex Browser use to support an option to open and use a user-selected external/system browser, such as Chrome, Safari, or Edge, instead of being limited to the built-in in-app browser.

The main reason is that many real workflows involve pages where the user is already signed in through their normal browser. The external browser often already has the required cookies, sessions, SSO state, password-manager flow, 2FA trust state, and existing login records. With the current built-in browser, users often need to sign in again, and some authentication flows may not work as smoothly as they do in a regular browser.

Why this would help

• Local development apps, admin dashboards, internal tools, cloud consoles, and SaaS products often require login before the useful page can be tested.
• Users may already be authenticated in Chrome/Safari/Edge, so reusing that session would save time and reduce friction.
• It would make Browser use more practical for real-world debugging and product testing, especially when pages depend on cookies or account-specific state.
• It would avoid repeatedly logging in inside the in-app browser just to let Codex inspect or interact with a page.

Suggested behavior

• Add a “Use external browser” or “Open in system browser” mode for Browser use.
• Allow the user to select a browser/profile, for example Chrome, Safari, Edge, or the system default browser.
• Let Codex interact with a specific launched tab/window in that browser context, after explicit user permission.
• Keep the built-in browser as the default/sandboxed option for users who prefer isolation.
• Make this opt-in per thread, per site, or per session, with a visible indicator that Codex can view/control that browser tab.
• Provide a clear way to stop/revoke control at any time.

Security/privacy expectations

This should not silently read all browser data or cookies. The safer version would be an explicit, user-approved external-browser handoff where Codex can only see/control the specific tab or window that the user has opened for Browser use.