VS Code Codex extension log/error loop precedes renderer crashes

Summary

The VS Code Codex extension (openai.chatgpt) appears to enter a high-volume error/logging loop and shortly afterward VS Code's renderer process crashes.

I diagnosed this on a local macOS machine and uninstalling the extension stopped the loop immediately.

Environment

• VS Code: 1.116.0 (560a9dba96f961efea7b1612916f89e5d5d4d679, arm64)
• macOS: 26.3.1 (25D2128), Apple Silicon
• Extension: openai.chatgpt / Codex - OpenAI's coding agent
• Extension version observed: 26.415.20818-darwin-arm64

What happened

VS Code's main log showed repeated renderer crashes:

2026-04-16 00:12:56.071 [error] CodeWindow: renderer process gone (reason: crashed, code: 5)
2026-04-17 07:27:21.716 [error] CodeWindow: renderer process gone (reason: crashed, code: 5)
2026-04-18 00:40:51.645 [error] CodeWindow: renderer process gone (reason: crashed, code: 5)
2026-04-18 18:49:02.115 [error] CodeWindow: renderer process gone (reason: crashed, code: 5)

Immediately before the latest crash, the extension host log was repeatedly emitting this stack from the Codex extension:

RangeError: Set maximum size exceeded
    at Set.add (<anonymous>)
    at LS.handleCancel (~/.vscode/extensions/openai.chatgpt-26.415.20818-darwin-arm64/out/extension.js:233:24821)
    at Object.handleCancel (~/.vscode/extensions/openai.chatgpt-26.415.20818-darwin-arm64/out/extension.js:263:26949)
    at T_.handleMessage (~/.vscode/extensions/openai.chatgpt-26.415.20818-darwin-arm64/out/extension.js:263:27484)
    at t.handleMessage (~/.vscode/extensions/openai.chatgpt-26.415.20818-darwin-arm64/out/extension.js:263:69236)

The same RangeError: Set maximum size exceeded pattern appeared in several prior sessions, usually immediately before Extension host terminating: renderer closed the MessagePort.

The extension's own Codex.log was also filling rapidly with repeated messages like:

worker_rpc_response_error error={} method=stable-metadata workerId=git

During one live check, that log grew by about 327,510 bytes / 3,127 lines in 3 seconds. macOS also produced Code Helper (Plugin) disk-write diagnostics showing about 2.1 GB written by the plugin helper during an affected session. The live Code Helper (Plugin) process was also using elevated CPU.

Mitigation / confirmation

After uninstalling openai.chatgpt:

• The Codex.log stopped growing (0 bytes growth over a fresh 5-second check).
• The extension host no longer activated openai.chatgpt.
• VS Code CPU returned to idle.
• No new RangeError, worker_rpc_response_error, or renderer-crash lines appeared in the fresh VS Code log session.
• Restarting VS Code cleaned the removed extension folder from ~/.vscode/extensions.

Expected behavior

The extension should not enter an unbounded cancellation/error/log loop, and it should not contribute to renderer instability or multi-GB plugin-helper disk writes.

Notes

This report is based on local VS Code logs. I can provide additional sanitized excerpts if useful.