The Browser plugin does not work in the Codex desktop app on Windows.
Open 💬 4 comments Opened Jun 20, 2026 by 1954187736
Environment:
- Codex version: 26.616.5445.0
- Browser plugin: Installed and enabled
- Already tried: Reinstalling the plugin, restarting Codex, and starting a new conversation
- The issue is consistently reproducible
Steps to reproduce:
- Start a new conversation.
- Ask Codex to use the Browser plugin.
- Browser initialization fails.
Error:Mcp error: -32602: js: codex/sandbox-state-meta: missing field sandboxPolicy
Expected behavior:
The Browser plugin should connect successfully and control the in-app browser.
It appears that the sandbox-state metadata passed from the Codex desktop app to Browser/node_repl is missing the sandboxPolicy field.
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