Codex app crashes when embedded browser opens WebCodecs/canvas-capable pages

Tracked by [BRWPLAT-293 in the browser team]

What version of the Codex App are you using (From “About Codex” dialog)?

ChatGPT Powered by Codex & OWL Version 26.707.31428 Released Jul 9, 2026

What subscription do you have?

Pro $200

What platform is your computer?

Verified on both Windows and MacOS

What issue are you seeing?

Summary<br>The Codex Windows desktop app repeatedly loses its embedded Chromium GPU process when the in-app browser opens certain media/canvas-capable pages.<br>No video selection, upload, decode, or user interaction is required. Simply loading the official W3C WebCodecs demo reliably reproduced the same GPU-process crash previously observed while using ChatCut.<br>The GPU process then fails to relaunch. In some occurrences, the entire Codex AppX container terminates and Codex must be reopened.

Severity<br>High.<br>The issue can terminate the Codex desktop application, interrupt active work, and make the in-app browser unsafe to use with media-related web applications.<br>Environment<br>Application: OpenAI Codex for Windows<br>Codex version: 26.707.3748.0<br>Package: OpenAI.Codex_26.707.3748.0_x64__2p2nqsd0c76g0<br>Platform: Windows<br>OS build: 10.0.26200<br>Architecture: x64

What steps can reproduce the bug?

Open the in-app browser.

Navigate to:<br>[https://w3c.github.io/webcodecs/samples/video-decode-display/](<https://w3c.github.io/webcodecs/samples/video-decode-display/>)

Press Start.

What is the expected behavior?

App not crash

Additional information

Critical log excerpts<br>Codex logs use UTC timestamps. Local time was UTC−7.<br>Reproduction 1: W3C WebCodecs page, no interaction<br>No file was selected and Start was never pressed.<br>2026-07-10T23:54:34.077Z info<br>\[electron-message-handler\] IAB_LIFECYCLE renderer created browser sidebar webview<br>hostKind=right-panel<br>initialUrl=[https://w3c.github.io/webcodecs/samples/video-decode-display/](<https://w3c.github.io/webcodecs/samples/video-decode-display/>)<br>rendererWebContentsId=1<br>rendererWindowId=1

2026-07-10T23:54:34.178Z info<br>\[browser-sidebar-manager\] IAB_LIFECYCLE runtime attached browser sidebar webview<br>guestWebContentsId=5<br>ownerWebContentsId=1<br>windowId=1

2026-07-10T23:54:36.022Z info<br>\[browser-sidebar-manager\] browser sidebar dom-ready<br>interactionMode=browse<br>url=[https://w3c.github.io/webcodecs/samples/video-decode-display/](<https://w3c.github.io/webcodecs/samples/video-decode-display/>)

2026-07-10T23:54:43.687Z warning<br>Recoverable Chromium child process gone<br>exitCode=101457950<br>name=null<br>processType=GPU<br>reason=crashed<br>serviceName=GPU

2026-07-10T23:54:43.691Z warning<br>Recoverable Chromium child process gone<br>exitCode=18<br>name=null<br>processType=GPU<br>reason=launch-failed<br>serviceName=GPU<br>Timing:<br>Browser guest created: 23:54:34.077Z<br>Page reached DOM ready: 23:54:36.022Z<br>GPU process crashed: 23:54:43.687Z<br>GPU restart failed: 23:54:43.691Z<br>Time from DOM ready to crash: approximately 7.7 seconds<br>The page still showed Fetch, Demux, Decode, and Render as “Not started.”<br>Reproduction 2: ChatCut page<br>This produced the exact same GPU-process exit codes:<br>2026-07-10T23:29:07.075Z info<br>\[browser-sidebar-manager\] browser sidebar dom-ready<br>interactionMode=browse<br>url=[https://www.freeconvert.com/video-compressor](<https://www.freeconvert.com/video-compressor>)

2026-07-10T23:29:44.143Z info<br>\[browser-sidebar-manager\] browser sidebar dom-ready<br>interactionMode=browse<br>url=[https://app.chatcut.dev/](<https://app.chatcut.dev/>)

2026-07-10T23:29:44.249Z warning<br>Recoverable Chromium child process gone<br>exitCode=101457950<br>name=null<br>processType=GPU<br>reason=crashed<br>serviceName=GPU

2026-07-10T23:29:44.253Z warning<br>Recoverable Chromium child process gone<br>exitCode=18<br>name=null<br>processType=GPU<br>reason=launch-failed<br>serviceName=GPU<br>Timing:<br>ChatCut reached DOM ready: 23:29:44.143Z<br>GPU process crashed: 23:29:44.249Z<br>Time from DOM ready to crash: approximately 106 milliseconds<br>GPU replacement failed four milliseconds later<br>Windows then destroyed the Codex AppX container:<br>2026-07-10 16:29:45<br>Microsoft-Windows-AppModel-Runtime<br>Event ID: 217

Destroyed Desktop AppX container for package:<br>OpenAI.Codex_26.707.3748.0_x64__2p2nqsd0c76g0