[VS Code] Opening Codex sidebar terminates renderer on Ubuntu 26.04 / VS Code 1.129.0

What version of the IDE extension are you using?

Reproduced with:

• 26.715.31925
• 26.707.91948 (rollback)

Which IDE are you using?

Visual Studio Code stable:

Version: 1.129.0
Commit: 125df4672b8a6a34975303c6b0baa124e560a4f7
Architecture: x64

What platform is your computer?

Ubuntu 26.04 LTS (Resolute), Linux x64.

What issue are you seeing?

Opening the Codex sidebar causes the entire VS Code window renderer to terminate. Before termination, VS Code can show:

An error occurred while loading view: chatgpt.sidebarSecondaryView

The Codex extension itself activates successfully and starts codex app-server, but the renderer exits while the sidebar webview/resources are being created.

Relevant log excerpts:

[Codex.log]
Activating Codex extension
[CodexMcpConnection] Spawning codex app-server
[CodexMcpConnection] Initialize received id=1

[exthost.log]
ExtensionService#_doActivateExtension openai.chatgpt
Extension host terminating: renderer closed the MessagePort

[renderer.log]
potential listener LEAK detected
...
pde.doReadFileStream
pde.readFileStream
TQe.loadResource

[main.log]
CodeWindow: renderer process gone (reason: clean-exit, code: <unknown>)

In a clean test profile, the renderer exited about 10–13 seconds after launch/opening the Codex view.

What steps can reproduce the bug?

1. On Ubuntu 26.04 x64, install VS Code stable 1.129.0.
2. Install the official openai.chatgpt extension.
3. Open a workspace.
4. Click the Codex icon / open the Codex secondary sidebar.
5. The view reports chatgpt.sidebarSecondaryView failed to load, then the VS Code window terminates.

What is the expected behavior?

The Codex sidebar should render without terminating the VS Code renderer/window.

Additional information

Isolation already performed:

• VS Code with all extensions disabled remains stable.
• Codex activates and starts its app-server successfully; failure occurs when opening/rendering the Codex sidebar.
• Reproduces with a fresh --user-data-dir.
• Reproduces with X11 and --disable-gpu.
• Reproduces after disabling ESP32-related extensions, including with ESP-IDF excluded.
• Reproduces after rolling back Codex from 26.715.31925 to 26.707.91948.
• Reproduces after also rolling back Claude Code from 2.1.214 to 2.1.212.
• Extension auto-update was disabled before the final rollback test.
• Reproduces with an older isolated GDK Pixbuf library that does not load libglycin, so a secondary Ubuntu crash stack involving glycin does not appear to be the primary cause.
• Storage SQLite integrity checks passed; RAM, disk, and /dev/shm were healthy.

No private logs, workspace contents, or local user paths are included.