Agent chat: the gutter beside every part of the floating stack scrolls the transcript by teamleaderleo · Pull Request #23243 · manaflow-ai/cmux

teamleaderleo · 2026-10-21T09:13:37Z

Summary

In the agent chat, when the bottom stack floats over the transcript, the wheel in the gutter beside the composer's card already scrolls the transcript (Leo 2026-10-20: "if it's not in the composer it should just scroll"). Beside the stack's other parts it did not. The question card, the pull request dock, error cards and the agents pill are bands as wide as the pane, with their card inset. The wheel in a band's gutters or empty room hit the band and scrolled nothing.

The fix keeps the bands catching the pointer. The transcript rows under the stack are only masked (.acpmux-scroll[data-docked]), so a band that passed the pointer through would let a hover, click or drag in its empty room reach rows no one can see: link hover cards, hidden links, tool rows, text selection. Instead, wheelPassThrough.ts forwards a wheel whose target is a band itself (a direct child of the floating .acpmux-dock, not the composer and not the dictation notice) to the transcript, the way it already forwards the wheel over Jump to latest. It does this only when the band can't scroll itself (scrollHeight <= clientHeight), so a pull request dock or question card that overflows in a short pane keeps its own wheel, and a wheel there never scrolls both. Because the bands take the pointer, those two parts' scrollbars can be dragged again. The composer is unchanged: it passes the pointer through around its card and queue.

Changelog

Fixed: In an agent chat, scrolling beside the question card, the pull request bar, an error card or the agents pill now scrolls the conversation.

Testing

CMUX_BROWSER_TESTS=1 bun test test/agent-pane-dock-gutters.test.ts (CI web / react-apps-check, Chromium and WebKit). One chat shows every part of the stack at once:

the question (a pending permission)
the pull request dock (3 PRs)
an error card (Edit CLAUDE.md, which the browser host refuses)
the agents pill (2 running subagents)
the queue (2 prompts) and the composer's card
later in the test, the dictation notice

For each part, the pointer 8 px left of the card reaches the band (for the composer's queue and card, the transcript) and the wheel there scrolls the transcript both ways. The same holds in the empty room right of a PR chip and right of the agents pill, where elementFromPoint must not be inside .acpmux-scroll. The wheel over a card moves nothing. The agents list dialog takes the pointer. In a 440 px pane, the wheel over the overflowing PR dock scrolls only the dock, and for each overflowing part the point 3 px in from the band's right edge (its scrollbar) reaches the band.

First approach (bands pass the pointer through), test-only head 1d4d573: red in both engines. Fixed at 3b3c868 (PASS). Review found the hidden-row problem above.
Test for the reviewed approach, test-only head 9895107: red in both engines:
- The gutter beside the question card reached transcript, not band (line 250).
- The pill's gutter with its list open reached transcript (line 309).
- The PR dock's scrollbar reached transcript (line 342).
Fix 02fff40, then test-only follow-ups at 8ea0f9a (the question card asserts only that the transcript stays still) and 560891d (each wheel waits until the transcript holds still, after a WebKit run measured a glide that was still moving). On 560891d: PASS test/agent-pane-dock-gutters.test.ts (react-apps-check shard 3, both engines).

Observed / Not run

Observed: the CI logs above. On 02fff40 the two main cases passed in both engines. The short-pane case failed only on the question card's own scroll: the wheel over its rows moves neither the card nor the transcript. Wheels over a band's contents are handled the same way as on base, so this isn't caused by this PR. The test now asks only the PR dock to scroll alone, and asks the question card only that the transcript stays still and its scrollbar takes the pointer.

On 560891d, the remaining react-apps-check reds are secret-card and timeouts in composer-draft-wrap and composer-row-layout. Earlier heads also had reds in files this PR doesn't touch:

agent-pane-scrollbar-full-height
gallery-agent-pane-entries, gallery coverage
pane-english (run-board)
the + is its glyph and Add tooltip cases
pet picker and Chiefs list cases
the motion categories case
timeouts in composer-draft-wrap, composer-type-scale and composer-row-layout

Not run: nothing ran locally; browser tests run only on CI. The recap card (behind a Debug toggle) and the folder-choice, worktree and btw notices (shown only before a chat starts or with side sessions on) aren't in the fixture. They are bands of the same shape and get the same handling. Dragging a scrollbar is checked only through elementFromPoint, not with a real drag.

Agent session: cosmic-gray

🤖 Generated with Claude Code

…scrolls the transcript A browser test (Chromium and WebKit) with one chat that shows every part of the bottom stack at once: the question, the pull request dock, an error card, the agents pill, the queue and the composer's card, then the dictation notice. Beside each part's card the pointer reaches the transcript and the wheel scrolls it; over the card it does not. Red on this head: the question, pull request dock, error card and agents pill bands take the pointer across the pane's width. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

teamleaderleo · 2026-10-21T09:13:51Z

Owned by composer-scroll on cosmic-gray · session

github-actions · 2026-10-21T09:14:42Z

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review 1f6db4e: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr23243 -f ref=cmux/dock-gutters-scroll -f platform=macos -f backend_mode=local

Probably yours: streaming-text-frames.test.ts, streaming-text-frames.test.ts fails here but not on main's latest full suite.

CI failed on 1f6db4ed39 (run 39612738079 attempt 1): 1 code, 1 unknown.

Job	Verdict	Why
web / react-apps-check (2)	code	a web test failed
web / react-apps-check	unknown	no known signature; failed step: `Check webview test shards`

Failures:

new in this PR streaming-text-frames.test.ts chromium claude: a long reply streams within the frame budget, with no shift above its tail: failed (job)
new in this PR streaming-text-frames.test.ts webkit claude: a long reply streams within the frame budget, with no shift above its tail: failed (job)

Matched log lines

web / react-apps-check (2): (fail) chromium claude: a long reply streams within the frame budget, with no shift above its tail [34660.65ms]

Not re-run automatically: web / react-apps-check (2), web / react-apps-check are not machine failures.

Written by scripts/ci/classify_failures.py (ci-failure-attribution.yml); signatures are its SIGNATURES table. A machine verdict is the runner's fault, not this PR's; yours means the failing file is one this PR changes, also red on main that main's latest full suite fails the same way, seen on other PRs that it failed on another pull request's run lately.

red: web / Web status; NEW: green on the base 95c0d1f; do not merge until green; see lane-rules
red: web / react-apps-check; no finished base run on 95c0d1f to compare; do not merge until green; see lane-rules
red: web / react-apps-check (2); no finished base run on 95c0d1f to compare; do not merge until green; see lane-rules

CI fast guards failed on 1f6db4ed39 (https://github.com/manaflow-ai/cmux/actions/runs/39612738079). It does not block the merge; a red guard merged into main breaks it for every open PR.
The log named no failed step; see the run.

Agents: python3 scripts/ci/guard_attribution.py fix applies the mechanical fixes locally.

Gallery before/after for 1f6db4e: 16 states rendered, 4 images differ, 625 more touched states not rendered. Images are in the run's artifact, not on this public PR.

gh run download 39612737705 -R manaflow-ai/cmux -n gallery-advisory-23243-1f6db4ed39754cac63ba6e0e83705afe29d7608c (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
`agent-pane.streaming-text/claude`	Apple System Colors	changed	4.12%	own `bottomStack.css`
`agent-pane.streaming-text/claude`	Apple System Colors Light	changed	0.0006%	own `bottomStack.css`
`agent-pane.streaming-text/codex`	Apple System Colors Light	changed	0.0033%	own `bottomStack.css`
`agent-pane.streaming-text/codex`	Apple System Colors	changed	0.0017%	own `bottomStack.css`
`agent-pane.chat-width/standard`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.chat-width/standard`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.chat-width/wide`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.chat-width/wide`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.chat-width/wide-blocks`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.chat-width/wide-blocks`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.composer-floats/scrolled-to-end`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.composer-floats/scrolled-to-end`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.composer-floats/composer-grown`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.composer-floats/composer-grown`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/new-chat`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/new-chat`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/after-turn`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/after-turn`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/working`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/working`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/typing-in-dock`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/typing-in-dock`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/long-title`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.docked-chat/long-title`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/local-queue`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/local-queue`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/huge-blue`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/huge-blue`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/cloud-fair-share`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.orchestration-lab/cloud-fair-share`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.streaming-follow-motion/stream`	Apple System Colors Light	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)
`agent-pane.streaming-follow-motion/stream`	Apple System Colors	unchanged	0%	imports `wheelPassThrough.ts` (1 hops)

_{Pick other states with a Gallery: entry.id, entry.id/variant line in the PR body.}

…s only drawn parts Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

teamleaderleo · 2026-10-21T09:21:19Z

Bead cx-htb3f created for this PR by the cmux coordinator.

blacksmith-sh · 2026-10-21T09:27:57Z

Found 3 test failures on Blacksmith runners:

Failures

Test	View Logs
`---/---`	View Logs
`test/streaming-text-frames.test.ts/streaming-text-frames.test`	View Logs
`test/streaming-text-frames.test.ts/streaming-text-frames.test`	View Logs

^{Need help on this PR? Tag @codesmith-bot with what you need.}

…crolls the transcript The floating bottom stack passed the pointer through only around the composer's card: its other parts (the question card, the pull request dock, error cards, the agents pill) are bands the pane's width wide with their card inset, and the band took the pointer, so the wheel in the gutter beside them scrolled nothing. Now every part's band passes the pointer through and what it holds takes it, the rule the composer had, so a new part gets it too. Text-only parts and notice lines keep the whole band. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

teamleaderleo · 2026-10-21T09:51:20Z

codex-review: SHIP at 3b3c868

Reviewed the current diff, its focused tests, and the affected call paths; no correctness bug found.

…n their empty room scrolls the transcript Review of #23243: with the bands passing the pointer through, every empty spot in a band (right of the agents pill, right of a pull request's chip, its padding) reached the transcript rows hidden under the stack, so hover, click and drag acted on unseen rows. The test now asks that those spots reach the band while the wheel there still scrolls the transcript, and that a part scrolling in a short pane scrolls alone with its scrollbar under the pointer. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

…l on to the transcript Review of #23243: the transcript's rows under the floating stack are only masked, so a band that passed the pointer through let a hover, click or drag in its empty room reach rows no one sees. The bands take the pointer again (the composer still passes it through around its card), and wheelPassThrough.ts forwards a wheel over a band itself to the transcript, as it does over Jump to latest, unless the band scrolls itself; the pull request dock's and question card's scrollbars take the pointer again. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

teamleaderleo · 2026-10-21T11:13:30Z

cmux-next fast gates / fast gates is red on 12 of 18 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

…croll alone; the question card only keeps the transcript still Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

…hold still before the next measure Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

…k-gutters-scroll

… a timer The fixed-waits ratchet (#23365): wheelAt counts animation frames until the transcript and the stack's scrollers hold still for 12 frames, or 30 frames pass with nothing moved. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

cursor · 2026-10-21T13:58:45Z

Bugbot needs on-demand usage enabled

Bugbot uses usage-based billing for this team and requires on-demand usage to be enabled.

A team admin can enable on-demand usage in the Cursor dashboard.

…ents pill (#23526) #23104 replaced the agents pill with the tray of running work (on by default) after #23243 landed this file, so the file's setup waited for a pill that never shows and hit the runner's 120 s limit on every run. The file now waits for the tray, expects it in the stack's order, and checks it as the dictation notice: the stack's gutter beside it passes through and scrolls the transcript, the tray takes the pointer and the wheel over it scrolls nothing. The pill's own list test goes with the pill. Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

github-actions · 2026-10-21T16:04:39Z

Shipped in:

cmux NEXT nightly 1.0.0-nightly.3962509665801 (ed547f0e27)
cmux NEXT nightly 1.0.0-nightly.3962960774501 (913f2e6d53)

teamleaderleo added risk:low Risk tier (docs/ci/risk-tiers.md) risk:normal Risk tier (docs/ci/risk-tiers.md) and removed risk:low Risk tier (docs/ci/risk-tiers.md) labels Oct 21, 2026

test(agent pane): the dock-gutters chat opens on its stack, and count…

1d4d573

…s only drawn parts Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Agent-Session: https://cmux.com/deeplink/agent?harness=claude&session=01a15bf1-fdc7-79b0-b869-8ac78b0edd90&host=cosmic-gray

teamleaderleo and others added 2 commits October 21, 2026 03:41

teamleaderleo and others added 4 commits October 21, 2026 05:12

Merge commit '95c0d1faa48e2214c37caf238d49d0a27bba75a1' into cmux/doc…

177fd70

…k-gutters-scroll

teamleaderleo merged commit b17a1dc into feat-cmux-next Oct 21, 2026

teamleaderleo deleted the cmux/dock-gutters-scroll branch October 21, 2026 14:39

teamleaderleo mentioned this pull request Oct 21, 2026

test(webviews): dock gutters covers the running-work tray, not the agents pill #23526

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Agent chat: the gutter beside every part of the floating stack scrolls the transcript - #23243

Agent chat: the gutter beside every part of the floating stack scrolls the transcript#23243
teamleaderleo merged 9 commits into
feat-cmux-nextfrom
cmux/dock-gutters-scroll

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