[Windows][Browser Control] Chrome navigates current tab to about:blank when taking over CNIPA trademark application pages

Resolved 💬 0 comments Opened Jun 30, 2026 by jiaoba66 Closed Jun 30, 2026

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

26.611.62324

What subscription do you have?

puls

What platform is your computer?

windows

What issue are you seeing?

Bug: Browser Control navigates Chrome to `about:blank` when taking over CNIPA Trademark Application pages on Windows

Summary

When Codex Browser Control takes over an already-open Chrome tab displaying the China National Intellectual Property Administration (CNIPA) Trademark Application System, Chrome immediately navigates the current tab to about:blank.

The browser page itself becomes blank (this is not only an internal Codex state), making browser automation impossible.

The issue is consistently reproducible.

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Environment

Operating System

Windows 11 Pro x64

Codex Desktop

Version: 26.611.62324
Release Date: 2026-06-17

Google Chrome

Version: 150.0.7863.0 (64-bit)

Codex Chrome Extension

Version: 1.1.5

---

Browser Configuration

Browser Control is enabled.

Codex Chrome Extension is installed and enabled.

Browser sessions are created successfully.

Computer Use sessions are created successfully.

Chrome Native Host appears to be functioning correctly.

---

Chrome Policies

Only one Chrome policy exists:

LocalNetworkAccessAllowedForUrls

No enterprise policies affecting extensions are configured.

Confirmed absent:

ExtensionSettings
ExtensionInstallForcelist
URLBlocklist
DeveloperToolsAvailability

---

Reproduction Steps

Launch Codex Desktop.
Enable Browser Control.
Open Google Chrome.
Navigate to the CNIPA trademark application system.
Log in normally.
Open any trademark application page.
Ask Codex to use the currently opened browser tab.

Example prompt:

Use the current browser tab.

Continue working on the currently opened page.

---

Expected Result

Codex should attach to the existing Chrome tab and continue browser automation:

Read the page
Read DOM
Click controls
Fill forms
Upload files

without changing the page.

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Actual Result

Immediately after Codex begins controlling the page:

Chrome navigates the current tab to

about:blank

The original page disappears.
The browser window visibly becomes blank.
Codex reports that automation cannot continue because the page is now about:blank.

This happens before any form filling or clicking begins.

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Control Experiment

Browser Control works correctly on ordinary websites.

Example:

https://example.com

Prompt:

Open https://example.com and tell me the page title.

Codex successfully returns:

Example Domain

Therefore:

Browser Control works.
Chrome Extension works.
Browser sessions work.
Native Host works.

The issue appears to be specific to the CNIPA trademark application pages.

---

Additional Observations

Browser session folders are successfully created:

C:\Users\Administrator\.codex\browser\sessions

Computer Use session folders are also created:

C:\Users\Administrator\.codex\computer-use\sessions

The browser is redirected to about:blank immediately after takeover.

This is visible inside Chrome itself.

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What Has Been Ruled Out

The following have already been verified:

Windows installation
Chrome installation
Chrome version
Codex Desktop installation
Codex Chrome Extension installation
Browser permissions
Chrome enterprise policies
Browser session creation
Computer Use session creation

---

Suspected Cause

The issue appears during browser takeover of the CNIPA trademark application pages.

Possible causes include:

Browser session initialization failure
Chrome DevTools Protocol target replacement
Content script injection failure
COOP / COEP compatibility
Cross-origin security interaction
Browser Control takeover regression

The browser itself navigates to about:blank.

This is not merely an internal Codex state.

---

Frequency

100% reproducible.

The issue occurs every time Browser Control attempts to take over the trademark application page.

---

Attachments

Attached screenshots include:

Codex Desktop version
Chrome version
Browser Control settings
Chrome Extension settings
chrome://policy
Browser session folders
Computer Use session folders
Screenshot showing Chrome becoming about:blank

---

Minimal Reproduction

Windows 11

↓

Codex Desktop 26.611

↓

Chrome 150

↓

Open CNIPA trademark application page

↓

Ask Codex to use the current browser tab

↓

Chrome immediately navigates to about:blank

---

Additional Notes

I would be happy to provide additional logs, SQLite databases, or test experimental builds if needed.

What steps can reproduce the bug?

Launch Codex Desktop on Windows 11.

Enable Browser Control.

Open Google Chrome.

Navigate to the China National Intellectual Property Administration (CNIPA) Trademark Application System:

https://sbj.cnipa.gov.cn/

Open any trademark application page.

Ask Codex to use the current browser tab (or continue working on the current page).

Codex begins taking control of the browser.

Immediately after takeover, Chrome navigates the current tab to:

about:blank

The original page disappears and browser automation cannot continue.

The issue is reproducible 100% of the time.

Control experiment:
The same Browser Control works correctly on https://example.com, where Codex can successfully read the page title ("Example Domain"). The problem only occurs on the CNIPA trademark application pages.

What is the expected behavior?

_No response_

Additional information

View original on GitHub ↗