ChatGPT macOS 26.915.31945: Codex renderer repeatedly white-screens; Renderer reaches ~120% CPU

Summary

The current ChatGPT desktop app on macOS repeatedly gets stuck in the Codex view with a white page / centered logo. This happens frequently enough to block normal work.

Force-quitting only the high-usage Codex (Renderer) process in Activity Monitor immediately restores the Codex UI. The main ChatGPT app does not need to be quit.

Environment

• ChatGPT desktop app: 26.915.31945
• macOS: 26.6.2 (25G83)
• Apple Silicon / ARM64
• Codex Renderer identifier: com.openai.codex.helper.renderer
• Codex Framework / Renderer version: 153.0.8010.48 (8010.48)

Observed behavior

While the UI is stuck on the white page / centered logo, Activity Monitor has shown:

• Codex (Renderer) sometimes reaching ~120% CPU
• Codex (Service) around 37.5% CPU
• other renderer processes around 26.2% and 10.5% CPU
• Codex (Service) around 11% GPU

A macOS process sample taken from the affected renderer reported:

• Physical footprint: 3.2 GB
• Peak physical footprint: 4.7 GB
• Renderer had been running for only a few minutes when sampled

The sample shows heavy Chromium/V8 renderer activity, including V8 serialization/deserialization, compositor activity, GC/finalizer paths, PNG/EXIF-related work, etc.

Reproduction

1. Open the current ChatGPT desktop app.
2. Switch to / work in Codex normally.
3. After some use, the Codex page frequently becomes white with the centered logo and never finishes loading.
4. Leave the ChatGPT app open.
5. Open Activity Monitor.
6. Force quit only the active/high-usage Codex (Renderer) process.
7. The Codex page immediately returns to normal.

The problem then comes back again later during normal use.

Expected behavior

Codex should not enter a renderer state where the UI stops painting and remains on a white/logo screen.

If the renderer encounters an unrecoverable UI state, it should restart/recover automatically instead of requiring the user to kill the renderer process manually.

Impact

This happens repeatedly and makes the desktop Codex workflow unreliable for sustained work.

Diagnostic signal

The strongest signal is that killing only Codex (Renderer) fixes the UI instantly, while the rest of ChatGPT/Codex stays alive.

Combined with:

• renderer CPU sometimes reaching ~120%
• 3.2 GB current / 4.7 GB peak renderer memory footprint

this looks consistent with a renderer-side hang and possibly a runaway loop and/or memory-growth issue.

A full macOS sample report is available if maintainers want it.

Start by reproducing the Codex white-screen state on the listed ChatGPT and macOS versions, then review the available macOS sample report and renderer CPU and memory observations. Done means the Codex UI continues painting during sustained use or recovers automatically without manually killing the Codex (Renderer) process; no source file or test is named.