Issue: Browser tool fails to start due to missing X server
Resolved 💬 4 comments Opened Feb 6, 2026 by otto-apoc Closed Jun 12, 2026
💡 Likely answer: A maintainer (etraut-openai, contributor)
responded on this thread — see the highlighted reply below.
What version of Codex CLI is running?
codex-cli 0.98.0
What subscription do you have?
gpt-5.2-codex
Which model were you using?
gpt-5.2-codex
What platform is your computer?
Linux 6.8.0-90-generic x86_64 x86_64
What terminal emulator and version are you using (if applicable)?
Gnome Terminal
What issue are you seeing?
Missing X server to start the headful browser. Either set headless to true or use xvfb-run to run your Puppeteer script.
What steps can reproduce the bug?
- Call
mcp__chrome-devtools__new_pagewith any URL - Wait for the browser to launch
What is the expected behavior?
The browser starts successfully and opens the page
Additional information
_No response_
4 Comments
Based on the symptoms, this sounds like an issue with the MCP server, not with Codex. Can you explain why you think this is a Codex issue?
Because I haven't encountered this issue in opencode, claude code, and gemini. It only appears in codex that there is no X11 environment, but in reality, there is
Another issue is that during use, it always prompts that DNS cannot be resolved. As I am using it in my company, I believe it is a sandbox problem. How can I make Codex use the local configuration to resolve DNS for this problem?
Closing as a duplicate of #5166.