Computer Use get_app_state for Chrome returns cgWindowNotFound while Chrome is running

What version of the Codex App are you using?

Codex Desktop 26.623.61825 / build 4548

Computer Use helper: 1.0 / build 857

What platform is your computer?

• macOS 15.7.7 build 24G720
• Apple Silicon / arm64

What issue are you seeing?

Computer Use cannot attach to Google Chrome in a normal unlocked desktop session. Chrome is running and visible to the app inventory, but get_app_state fails before returning a screenshot or accessibility tree.

The same failure reproduces with all three Chrome identifiers:

mcp__computer_use.get_app_state({ app: "Google Chrome" })
=> Computer Use server error -10005: cgWindowNotFound

mcp__computer_use.get_app_state({ app: "com.google.Chrome" })
=> Computer Use server error -10005: cgWindowNotFound

mcp__computer_use.get_app_state({ app: "/Applications/Google Chrome.app" })
=> Computer Use server error -10005: cgWindowNotFound

At the same time, mcp__computer_use.list_apps() reports Chrome as running:

Google Chrome — /Applications/Google Chrome.app/ — com.google.Chrome [running]

Chrome is also scriptable outside the Computer Use path: AppleScript can query the active tab URL and title successfully. This points away from Chrome being absent or crashed, and toward the Computer Use window lookup / attach path.

What steps can reproduce the bug?

1. Open Codex Desktop on macOS.
2. Open Google Chrome and make sure it has a normal browser window.
3. From a Codex thread with the Computer Use plugin available, call:

mcp__computer_use.list_apps()
mcp__computer_use.get_app_state({ app: "Google Chrome" })
mcp__computer_use.get_app_state({ app: "com.google.Chrome" })
mcp__computer_use.get_app_state({ app: "/Applications/Google Chrome.app" })

1. Observe that list_apps sees Chrome, but each get_app_state call returns cgWindowNotFound.

What is the expected behavior?

Computer Use should attach to the visible Chrome window and return a screenshot and accessibility tree, or return a more specific diagnostic explaining why the visible/running app is not eligible for attachment.

What is the actual behavior?

Computer Use returns:

Computer Use server error -10005: cgWindowNotFound

No screenshot or accessibility tree is returned.

Related issues checked

I searched existing issues before filing. These look related but not exact duplicates:

• #27829: Appshots fail with cgWindowNotFound across apps. This report is specifically the MCP get_app_state path for Chrome.
• #26743 and #24086: locked Computer Use failures with cgWindowNotFound. This report was observed in an unlocked active desktop session.

If maintainers prefer this folded into #27829, that is fine; I filed separately because the failure is in direct Computer Use get_app_state for Chrome rather than Appshot hotkey capture.

Privacy / redaction note

I intentionally omitted the actual Chrome URL/title and local project details. The important observation is only that AppleScript could read Chrome's active tab while Computer Use could not attach.