/Tech2h ago

OpenAI launches Codex browser developer mode with Chrome DevTools Protocol integration for 2x faster automation

It lets the model inspect runtime errors and DOM state

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Original post

Introducing developer mode for browser use in Chrome and the Codex in-app browser.

Codex can use the Chrome DevTools Protocol (CDP) to debug browser issues by profiling JavaScript performance and inspecting console output, network traffic, and page state.

5:15 PM · Jun 11, 2026 · 52.5K Views
Sentiment

Positive users hail Codex's new Chrome Developer Mode and CDP support as a huge debugging improvement, while negative users complain about unrelated bugs in Computer Use and demand the return of 4o.

Pos
50.4%
Neg
49.6%
35 comments with sentiment.
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VIEWS3.1KLIKES21RETWEETS1
jason@jxnlco

Great ship by the browser team! Make sure to give @JamesZmSun a follow!

Introducing developer mode for browser use in Chrome and the Codex in-app browser.

Codex can use the Chrome DevTools Protocol (CDP) to debug browser issues by profiling JavaScript performance and inspecting console output, network traffic, and page state.

2hViews 3.1KLikes 21Bookmarks 1
BOOKMARKS4

https://developers.openai.com/codex/app/browser#developer-mode

2hViews 2KLikes 21Bookmarks 4
REPLIES2
Dickson Pau@DicksonPau

@JamesZmSun Can someone please take a look at the bug on Locked Computer Use please?? It’s been out for a few weeks not, but the bug persists

1hViews 345Likes 1
Justin Rushing@justin_rushing

@Ray_DaHero @OpenAIDevs @reach_vb We’re aware of this issue and working to resolve it!

1hViews 33Likes 2Bookmarks 1
Carlos Funelas@cartchstudio

Be careful when using CDP with Chrome.

CDP is powerful. If you expose your everyday Chrome session, an agent may be able to inspect or control tabs, cookies, localStorage, network traffic, console output, and page state.

Use a dedicated throwaway profile, not your personal one.

Codex's in-app browser is the safer default if you don't need real-profile access.

59mViews 168Likes 3

@DicksonPau @JamesZmSun Sorry! What’s the bug?

59mViews 12
Ray@Ray_DaHero

@OpenAIDevs I have completely lost access to In-App Browser and Computer use after this update instead... Can this be looked into?

#Codex #OpenAI @reach_vb

2hViews 349Likes 1
Dickson Pau@DicksonPau

1. Locked Computer Use runtime failure: Computer Use works while the Mac is unlocked. After locking the Mac, list_apps still works, which means the helper is reachable, but get_app_state("Finder") hangs and times out after 120 seconds. So the locked-screen app/window reading path is failing.

2. Install / authorization verification issue: The lock-screen component appears to be in an inconsistent state. The installer/status check has at times reported not-installed even though the SecurityAgent plugin bundle exists, and the installed authorization plugin fails codesign verification with “invalid signature.” So the system may not be reliably proving that the lock-screen authorization component is correctly installed, trusted, or activated.

49mViews 7
Tom Rush@tr4777

@OpenAIDevs Cool, making web app then (+iOS) 😂 thx @dkundel

2hViews 170Likes 1
Dickson Pau@DicksonPau

@AriX @JamesZmSun Let me DM you thank you!

53mViews 3
Diam@diamai_

@OpenAIDevs Good. Now Codex can see the same broken page the rest of us stare at for 20 minutes.

2hViews 392
David Stark@stark4833

@OpenAIDevs Oh okay more stuff nobody asked for. How about you listen to your customers and give us back 4o. #keep4o

2hViews 112Likes 1
Superhero "Crypto" Ninja@SuperheroCrypto

@JamesZmSun Awesome! Is it smart enough to use the right chrome profile when running multiple chats that should use different profiles?

1hViews 346
Francesco@francedot

@JamesZmSun great work!

1hViews 336
Crypto Newspaper@Joseamcdonals89

@OpenAIDevs When available in Spain for pro max ultra users ?

1hViews 302
bitslix@bitslix

@OpenAIDevs But you know that a JavaScript console log can easily eat up to 5Mio token in 30 error calls?

2hViews 149
sennn@_hibana01

@OpenAIDevs amazing new feature! can we also see the image of the corgi that was generated perchance?😅

2hViews 125
rmx_@_rmx_m

@OpenAIDevs Hey! I built that from scratch last month!!! Thank you very much!!

2hViews 78
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