fix(terminal): prevent Herdr rendering freezes by binaricat · Pull Request #2472 · binaricat/Netcatty

binaricat · 2026-07-24T15:03:54Z

Summary

keep xterm writes on the normal asynchronous completion path so full-screen Herdr frames cannot strand the renderer acknowledgement queue
drain pending output safely before resize, hibernate, snapshots, close, and attach handoff
coordinate output pauses across main and popup windows, including worker mode and crash recovery
retain the WebGL atlas-capacity recovery for the separate long-running renderer freeze
add regressions for Herdr-style frames in visible, hidden, reveal, resize, handoff, and worker scenarios

Root cause

There were two independent freeze modes.

The immediate, consistently reproducible stall was caused by Netcatty forcing xterm private synchronous parser drains while a normal asynchronous write was active. xterm documents that path as unreliable. It could strand the queued completion callback, so Netcatty never acknowledged the large frame and the backend stayed paused after the first partial render.

A separate long-running WebGL issue could exhaust the renderer atlas capacity during sustained glyph churn. This remains covered by the reviewed xterm backport and a real Electron pixel-level regression test.

Validation

local Codex CLI review on the final head: no actionable regressions
two independent review agents: CLEAN
Herdr focused regression repeated 10/10 on the final test fix
terminal-focused tests: 129/129 passed
main-process and worker flow tests: 72/72 passed
WebGL patch tests: 7/7 passed
real Electron/WebGL overflow regression: passed
current-head GitHub lint-and-test: passed
npm run lint
npm run build
git diff --check
restarted the current worktree with npm run dev for manual Herdr verification

Closes #2455

binaricat · 2026-07-24T15:23:12Z

@codex review

chatgpt-codex-connector · 2026-07-24T15:28:55Z

Codex Review: Didn't find any major issues. Hooray!

Reviewed commit: bf58324c80

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: bf58324c80

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

binaricat · 2026-07-24T15:54:12Z

@codex review

chatgpt-codex-connector · 2026-07-24T15:59:41Z

Codex Review: Didn't find any major issues. Keep it up!

Reviewed commit: defbb95e16

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

binaricat · 2026-07-24T16:43:39Z

@codex review

chatgpt-codex-connector · 2026-07-24T16:47:55Z

Codex Review: Didn't find any major issues. Swish!

Reviewed commit: b1a6e28975

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

binaricat · 2026-07-24T18:03:59Z

@codex review

binaricat · 2026-07-24T18:03:59Z

@codex review

chatgpt-codex-connector · 2026-07-24T18:04:16Z

Codex Review: Something went wrong. Try again later by commenting “@codex review”.

Unknown error

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

binaricat · 2026-07-24T18:05:05Z

@codex review

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 4f67c43e4a

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

netcatty-bot · 2026-07-24T18:13:18Z

Codex only reported P3 nitpicks (no P0–P2). Automatic fix stopped; a maintainer can decide whether to polish further.

binaricat · 2026-07-24T18:15:42Z

@codex review

binaricat · 2026-07-24T18:16:06Z

@codex review

chatgpt-codex-connector · 2026-07-24T18:23:25Z

Codex Review: Didn't find any major issues. Chef's kiss.

Reviewed commit: 54e1ab1fac

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

binaricat added the automation:codex-loop Own/bot PR waiting on Codex review↔fix loop label Jul 24, 2026

netcatty-bot marked this pull request as ready for review July 24, 2026 15:29

binaricat added 2 commits July 24, 2026 23:31

fix(terminal): prevent Herdr rendering freeze

0f5a12e

test(terminal): harden xterm overflow coverage

7806142

chatgpt-codex-connector Bot reviewed Jul 24, 2026

View reviewed changes

Comment thread scripts/patch-xterm-webgl-atlas.cjs Resolved

test(terminal): stabilize WebGL overflow probe

defbb95

binaricat force-pushed the codex/fix-herdr-xterm-freeze branch from bf58324 to defbb95 Compare July 24, 2026 15:46

binaricat marked this pull request as draft July 24, 2026 15:46

binaricat marked this pull request as ready for review July 24, 2026 15:49

binaricat marked this pull request as draft July 24, 2026 15:54

fix(terminal): keep visible xterm writes asynchronous

b1a6e28

netcatty-bot marked this pull request as ready for review July 24, 2026 16:56

binaricat added 5 commits July 25, 2026 01:00

fix(terminal): avoid interrupting xterm writes

24eb5e3

fix(terminal): reject incomplete output drains

6ab1f9c

fix(terminal): keep failed snapshots atomic

9105ce9

fix(terminal): cover Herdr rendering freezes

fd1635a

fix(terminal): arbitrate pause leases in main

4f67c43

binaricat marked this pull request as draft July 24, 2026 18:03

binaricat changed the title ~~fix(terminal): prevent Herdr rendering freeze~~ fix(terminal): prevent Herdr rendering freezes Jul 24, 2026

chatgpt-codex-connector Bot reviewed Jul 24, 2026

View reviewed changes

Comment thread components/terminal/runtime/terminalSessionAttachment.test.ts Resolved

netcatty-bot added ready-for-human Requires human implementation and removed automation:codex-loop Own/bot PR waiting on Codex review↔fix loop labels Jul 24, 2026

test(terminal): keep Herdr timeout active

54e1ab1

binaricat added the automation:codex-loop Own/bot PR waiting on Codex review↔fix loop label Jul 24, 2026

netcatty-bot marked this pull request as ready for review July 24, 2026 18:24

binaricat merged commit 093c997 into main Jul 25, 2026
55 of 57 checks passed

binaricat mentioned this pull request Jul 25, 2026

fix(terminal): prevent coalescer wake-up loss stalling TUI output #2470

Merged

binaricat deleted the codex/fix-herdr-xterm-freeze branch July 27, 2026 02:06

Conversation

binaricat commented Jul 24, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Root cause

Validation

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

netcatty-bot commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

binaricat commented Jul 24, 2026

Uh oh!

chatgpt-codex-connector Bot commented Jul 24, 2026

Uh oh!

Uh oh!

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

binaricat commented Jul 24, 2026 •

edited

Loading