Built-in Browser plugin fails to initialize with “Cannot redefine property: process”

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

• #32936
• #32925
• #32934

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same happening on mac os：
The built-in browser fails to initialize.

Steps to reproduce:

Run the following code through mcp__node_repl__js:

if (globalThis.agent?.browsers == null) {
const { setupBrowserRuntime } = await import(
"/Users/markliu/.codex/plugins/cache/openai-bundled/browser/26.707.71524/scripts/browser-client.mjs"
);
await setupBrowserRuntime({ globals: globalThis });
}

Actual error:

Cannot redefine property: process

The same error still occurs after running mcp__node_repl__js_reset and retrying the initialization.

Environment:

• Codex Desktop
• Browser plugin version: 26.707.71524
• macOS
• Date: July 14, 2026

Expected behavior:
setupBrowserRuntime should initialize successfully, allowing the built-in browser to be accessed through agent.browsers.get("iab").

Actual behavior:
Initialization fails because of a conflict involving the global process property. As a result, the built-in browser cannot be opened or controlled.

Solved on my end (locally)
https://github.com/openai/codex/issues/32941#issuecomment-4965299465

Independent Windows reproduction confirming this issue.

Environment:

• OS: Microsoft Windows NT 10.0.26200.0, x64
• Bundled Browser plugin: 26.707.71524
• Surface: Codex desktop in-app Browser

Reproduction:

1. Open an in-app Browser tab.
2. From a Codex task, initialize the Browser runtime using the official bundled browser-client.mjs and setupBrowserRuntime({ globals: globalThis }) workflow.
3. Initialization immediately fails with Cannot redefine property: process.
4. Reset the managed JavaScript session and repeat from a fresh state; the same error occurs.
5. Attempt control of an unauthenticated public site (yahoo.com) to exclude target-site authentication. The runtime fails before navigation, so the target URL is never reached.

This also reproduces when the visible tab is an authenticated session, confirming the problem is independent of page authentication or application code. The failure blocks any workflow requiring the authenticated in-app Browser, including browser-assisted market-data collection.

Expected: the trusted bundled Browser client should import and attach to the in-app Browser without attempting to replace the runtime's protected process global.

Additional Windows reproduction with a useful two-stage failure boundary.

Environment

• OS: Windows x64
• Codex Desktop package: OpenAI.Codex_26.707.9564.0_x64__2p2nqsd0c76g0
• ChatGPT.exe file version: 150.0.7871.115
• Bundled Browser plugin: 26.707.71524
• Browser client: ~/.codex/plugins/cache/openai-bundled/browser/26.707.71524/scripts/browser-client.mjs

The in-app Browser UI itself worked normally: pages loaded, the ChatGPT account was signed in, and the target conversation was visible. The Browser plugin files, manifest, skills, docs, assets, and browser-client.mjs were present and unmodified.

Stage 1: managed JS kernel failed before user code

Before a full Codex Desktop restart, the standard Browser bootstrap failed with:

failed to write kernel assets:
The system cannot find the path specified. (os error 3)

Even a minimal control-runtime expression that only returned cwd, tmpDir, and homeDir produced the same error. This indicates that this first failure occurred before Browser code or user JavaScript executed.

The following explicit paths existed at the time:

• browser-client.mjs
• %TEMP%
• C:\Users\fanmo\.codex

Therefore the missing path was likely an internal kernel-assets target rather than one of those visible paths.

Stage 2: restart restored the kernel, but Browser bootstrap still failed

After fully restarting Codex Desktop, simple Node-backed control code worked again. The kernel-assets error disappeared, but importing the official bundled Browser client and running:

const { setupBrowserRuntime } = await import(
  "C:/Users/fanmo/.codex/plugins/cache/openai-bundled/" +
  "browser/26.707.71524/scripts/browser-client.mjs"
);

await setupBrowserRuntime({ globals: globalThis });

consistently failed with:

Cannot redefine property: process

A clean JavaScript-kernel reset did not change the result.

Immediately after failure, none of the Browser globals had been created:

hasAgent: false
hasBrowsers: false
hasIab: false
hasBrowser: false

The same failure occurred both when attempting to bind an existing authenticated in-app Browser tab and when starting from a clean state before creating any new tab. Execution never reached browser discovery, agent.browsers.get("iab"), tab creation, or navigation.

Interpretation

This observation separates two layers:

1. A transient/stale managed-kernel initialization failure (failed to write kernel assets) that was cleared by a full application restart.
2. A stable Browser-client bootstrap incompatibility (Cannot redefine property: process) that remained after the managed kernel itself was functional.

The current bundled client assigns its own shim to globalThis.process / globalThis.global.process, while the managed runtime exposes a protected process surface. Combined with the cross-platform reports in this thread, this strongly suggests the persistent Browser failure is a plugin/runtime compatibility regression rather than a website, login, tab, sandbox-permission, or ordinary cache issue.

No plugin files or caches were modified or deleted. I am leaving the installation unchanged and waiting for an official fix.

Reproduced on a newer Windows Store build after a clean forced reinstall.

Environment:

• Windows: Microsoft Windows NT 10.0.26220.0 (AMD64)
• OpenAI.Codex: 26.707.9981.0
• OpenAI.ChatGPT-Desktop: 1.2026.190.0
• Codex CLI: 0.126.0-alpha.8
• Bundled in-app Browser plugin cache: browser-use/0.1.0-alpha2

Observed behavior:

• The documented Browser bootstrap fails immediately while importing scripts/browser-client.mjs.
• Error: Cannot redefine property: process
• The failure occurs before tab discovery or access to the target URL.
• Chrome browser-client initialization fails at the same stage.

Troubleshooting performed:

1. Reset the JavaScript kernel and retried from a fresh runtime.
2. Fully restarted Codex.
3. Confirmed Microsoft Store reported no newer update.
4. Forced a reinstall of the official Store package 9PLM9XGG6VKS.
5. Restarted Codex again and retried the in-app Browser bootstrap.

Result: the error persists unchanged. No project content, browser cookies, URLs, or account identifiers are involved in the reproduction.

Confirming the same regression on Windows 11 x64.

• Codex package: OpenAI.Codex 26.707.9564.0
• Browser plugin: 26.707.71524
• Error: TypeError: Cannot redefine property: process
• Stack location: browser-client.mjs:33:22
• The Browser client SHA-256 matches the trusted hash, ruling out local file corruption.
• In the same environment, plugin version 26.707.51957 successfully initialized the Codex in-app browser. Version 26.707.71524 now fails during module import, before URL navigation or authentication.
• Resetting the JavaScript runtime and restarting the app do not resolve it.

This appears to confirm a version-pairing regression between the bundled Browser client and the Node REPL runtime.

Additional Windows reproduction with a different app/plugin version pair.

Environment

• Platform: Windows x64
• Codex Desktop: 26.707.72221
• Bundled Browser/Chrome control package: 26.707.31428
• Observed: July 15, 2026 (UTC+8)

Reproduction and diagnostics

1. Start a Codex task and invoke the bundled in-app Browser.
2. Load the documented browser-client.mjs bootstrap and call setupBrowserRuntime({ globals: globalThis }).
3. Initialization fails immediately with:

Cannot redefine property: process

The failure occurs before browser discovery, tab creation, or navigation. Resetting the JavaScript runtime and fully restarting Codex Desktop did not help.

The bundled Chrome plugin fails at the same bootstrap stage with the same error, so this appears to be in the shared browser-control runtime rather than the in-app Browser backend itself.

After restarting Codex, this directory disappeared and was not restored:

%USERPROFILE%\.codex\plugins\cache\openai-bundled\browser

The local state indicates that automatic installation of the bundled Browser plugin is not disabled, but no Browser plugin directory or installation staging files are present after restart. The underlying codex-browser-app profile still exists, which suggests the Chromium profile is present while the Browser control plugin/bridge is unavailable.

A potentially related background-process error was also observed after restart:

CreateProcessAsUserW failed: 1312

Impact

Both the in-app Browser and Chrome automation surfaces are blocked, preventing local web application testing, navigation, screenshots, DOM inspection, and UI automation.

Follow-up to my earlier Windows report: https://github.com/openai/codex/issues/32935#issuecomment-4979228975

I found that the original Browser runtime incompatibility appears to be fixed in a newer bundled Browser plugin, but Codex Desktop did not update the runtime marketplace snapshot on my machine.

Version mismatch

• Codex Desktop package: OpenAI.Codex_26.715.2236.0_x64
• Browser plugin included in the installed application package: 26.715.21316
• Browser plugin exposed by the runtime bundled marketplace: 26.707.31428
• Browser plugin installed in the user cache: 26.707.31428

The relevant configuration in ~/.codex/config.toml pointed the openai-bundled marketplace to:

C:\Users\<user>\.codex\.tmp\bundled-marketplaces\openai-bundled

The Browser manifest in that marketplace still reported 26.707.31428, even though the current Codex application package already contained Browser 26.715.21316.

Because the marketplace version and cached version were both 26.707.31428, Codex treated the installed plugin as current. Deleting the cache, uninstalling/reinstalling the plugin, and restarting Codex only installed the same old version again from the stale marketplace.

Temporary workaround

The following manual workaround resolved the problem for me:

1. Uninstall the Browser plugin from Codex Settings.
2. Copy the newer browser plugin directory from the current Codex application package:

``text
C:\Program Files\WindowsApps\OpenAI.Codex_26.715.2236.0_x64__...\app\resources\plugins\openai-bundled\plugins\browser
``

1. Replace the stale Browser directory in the runtime marketplace:

``text
C:\Users\<user>\.codex\.tmp\bundled-marketplaces\openai-bundled\plugins\browser
``

1. Reopen Codex and reinstall Browser from Settings.

After reinstalling, Codex created the new cache directory for 26.715.21316.

Verification

Using Browser 26.715.21316, I successfully:

• initialized setupBrowserRuntime({ globals: globalThis });
• connected to the Codex in-app Browser;
• opened https://example.com/;
• read the page title and DOM;
• clicked the Learn more link and navigated to the IANA page;
• completed the test with no Browser console errors.

The Cannot redefine property: process error no longer occurs with this version.

This appears to be a bundled-marketplace refresh/synchronization problem rather than a missing fixed plugin. The fixed plugin was already present in the installed Codex package, but the user-level runtime marketplace remained stale and caused reinstallations to keep selecting the old version.

This is only a temporary workaround because the generated marketplace snapshot may be overwritten. Ideally, Codex Desktop should automatically refresh the runtime bundled marketplace whenever the application-bundled plugin version changes.