Codex Desktop: Browser Use / in-app browser disappears mid-session without user reload

What version of the Codex App are you using (From “About Codex” dialog)?

Codex Desktop 26.506.31004 / build 2604 on macOS arm64.

What subscription do you have?

ChatGPT account in Codex Desktop.

What platform is your computer?

macOS, Apple Silicon / arm64.

What issue are you seeing?

The built-in Browser Use / in-app browser works normally, then disappears again mid-session without a user reload.

Observed behavior:

• Browser Use is available and working in the current Codex Desktop session.
• I continue the same conversation and formulate the next prompt.
• Without manually reloading the app, changing settings, or intentionally detaching panes, Browser Use disappears again.
• Settings -> Browser use may then show the plugin as unavailable.

This is not just "Browser Use missing at startup". It can vanish between consecutive prompts in the same session.

The strongest evidence points to an internal Codex UI/plugin-state rehydration problem:

• the browser run is still healthy beforehand
• Codex then logs renderer detached visible browser sidebar webview
• immediately after, Codex refreshes plugin/feature state with plugin/list and experimentalFeature/list
• after that, Browser Use availability becomes inconsistent or disappears

What steps can reproduce the bug?

I do not yet have 100% deterministic repro steps, but this is the closest pattern I have:

1. Launch Codex Desktop on macOS arm64.
2. Use Browser Use normally on a local app in the in-app browser.
3. Continue the same thread with more prompts, especially after longer browser work / UI review.
4. At some point, without a manual reload, Browser Use disappears and Settings -> Browser use may show unavailable again.

One observed sequence on May 8, 2026:

1. Browser Use worked normally in an active thread.
2. The last browser turn ended cleanly.
3. A few minutes later, without me manually reloading Codex, the app internally detached the visible browser sidebar webview.
4. Codex immediately re-requested plugin and experimental feature lists.
5. Browser Use was then gone again.

What is the expected behavior?

Browser Use should remain available throughout the session unless the user explicitly disables it or the app clearly reports a hard failure.

If the browser sidebar/webview is internally remounted or detached, Codex should preserve Browser Use availability and recover cleanly instead of flipping the plugin back to unavailable.

Additional information

Relevant app state:

• Bundled browser-use plugin exists locally and is not missing from disk.
• Browser Use startup is otherwise healthy in logs when the feature is present.
• This does not look like a missing install or a local skill customization issue.

Strongest log evidence from the failing session:

• at 2026-05-08 20:45:47Z (2026-05-08 22:45:47 CEST), Codex logged:
• renderer detached visible browser sidebar webview
• immediately after:
• method=plugin/list
• method=experimentalFeature/list

This suggests:

1. the visible browser sidebar/webview detaches unexpectedly
2. Codex rehydrates plugin/feature state
3. Browser Use availability is recomputed incorrectly

Temporary workaround that consistently restores Browser Use on this machine:

• quit Codex
• reset Codex local UI/cache state:
• ~/Library/Application Support/Codex/Local Storage/leveldb
• ~/Library/Application Support/Codex/Session Storage
• ~/Library/Application Support/Codex/Preferences
• /tmp/codex-browser-use
• relaunch Codex

That workaround restores Browser Use without changing account auth, plugin bundles, or local skills, which makes this look like a Codex Desktop state-management bug rather than a setup problem.

Related but not identical open issues I found:

• #21440 Browser Use disappeared from Codex App despite enabled feature flags
• #20743 Browser Use loses active pane binding after chat/browser detach

This report is different because the plugin disappears again without a user-initiated reload or explicit pane detach, and the settings page itself can revert to unavailable afterward.