[teamleaderleo]

Leo's words:

why the f*** did you guys ff***ing ellipsis EVERYTHING WITH NO WAY TO EXPAND WHAT WAS SAID TO SEE

AND IT'S SO F***ING AWKWARD TO SEE THEM THERE AT THE BOTTOM SINCE WHEN I EXPAND THEM IT JUMPS ME DOWN AND WHEN I COLLAPSE IT JUMPS ME UP

#28780 carried this PR's earlier head (5e59e44) to feat-cmux-next: every cut row opens to its whole text, every toggle holds its place, and the collapse room. This PR is now the remainder. It holds the toggle-hold fixes made after that head, merged with the current base. Its diff against base is about 60 lines.

What this changes

• A fixed minimum hold, not one that keeps extending (foldAnchor.ts). Base extends a hold by 150 ms every time its line moves, up to 1.5 s. While the view was scrolled to a tall prompt, that kept re-placing the prompt under the pointer, and its Show less missed the click (transcript-fold-anchor-browser: "Show less on a prompt several screens tall, with motion off" failed with it). Every hold now lasts max(foldMs + FOLD_SETTLE_MS, FOLD_HOLD_MIN_MS = 400 ms). A toggle with no fold under Reduce Motion, which used to get 150 ms, is still held while what it opened is measured and placed.
• A sideways wheel keeps the hold in both release paths (App.tsx cancelProgrammatic). Base exempted a horizontal wheel only in release. The user-scroll intent listener cleared the hold first, so scrolling a code block sideways still let go.
• The press place is never stale (App.tsx). A keyboard click (detail === 0) does not reuse an earlier, abandoned press, and pointercancel drops it. The row's own anchored-collapse event (holdAsked) keeps the click's pressed place instead of replacing it with where the line is now.
• A file link inside a tool line is not a toggle (NESTED_CONTROL gains [role="link"], the role WriteLabel's file name uses).
• No dangling aria-controls (ToolRow.tsx). Since every call opens, an opened call with no output names a body only when one is drawn.
• DiagramBlock's toggle carries data-fold-toggle too, like Wrap lines and Raw.

Stop and cleanup

Nothing new animates. A hold is a timestamp checked on each placement pass, with no timer. It ends at max(foldMs + FOLD_SETTLE_MS, FOLD_HOLD_MIN_MS) after the click, or at once on a vertical wheel, a key, a touch or a drag. The pointercancel listener is added and removed with the pointerdown and click listeners. Nothing runs per streamed token.

Tests

• conversation/foldAnchor.test.ts:
  • a toggle with no fold is held at least FOLD_HOLD_MIN_MS
  • a hold that puts its line back does not outlast its time
  • press, click, then the row's anchored-collapse event keeps the pressed place
  • a file link inside a tool line is not held
• conversation/TruncatedRowsReachable.test.tsx: an opened call's aria-controls names a body that exists, and a call with no output names none.
• Verified with cmux-ci on Linux Chromium:
  • typecheck, check:browser-lanes, check:fixed-waits, vp fmt
  • the acpmux conversation unit suites
  • 13 transcript browser suites: fold-keeps-place, fold-anchor-browser, follow-live, reading-place, queue-scroll-bottom, find-position, tool-group scroll, alignment and overlap, no-blank-space, incoming and received message disclosure, transcript-follow

Media

Linux Chromium gallery, agent-pane.tool-row-column (variant column), with the tool group opened. Captured through cmux-ci using a public gallery fixture. It shows what #28780 shipped and this PR keeps: every call row opens. This PR changes no layout.

Risk

Low. Hold timing only:

• Holds no longer extend while their line moves; they last at least 400 ms instead.
• A sideways wheel no longer releases a hold.
• A file link inside a toggle no longer starts one.

Performance

metric	before	after	delta	harness
work per streamed token in the transcript path	0 new	0 new	0	code read: the changes run only on clicks, presses, wheel events and placement passes, O(1) each

Follow-ups from review (not in this PR)

• Fold-room follow release when the transcript is shorter than the view: a no-output toggle can leave room above rowsEnd and stop following.
• outputSummary no longer caps text for briefs, steer and dispatch, not only reports.

Agent session: agent session

🤖 Generated with Claude Code

[github-actions]

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

Review 4a6266a: 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=pr28324 -f ref=claude-sr2/transcript-expand-anchor -f platform=macos -f backend_mode=local

Gallery before/after for 4a6266a: 16 states rendered, 0 images differ, 2654 more touched states not rendered. Images are in the run's artifact, not on this public PR; the independent review of this head reads them on its own, so the PR needs no hand-made screenshots of these states.

gh run download 41209715206 -R manaflow-ai/cmux -n gallery-advisory-28324-4a6266a623f54c1dc8508e0e1a57f7ca98742f92 (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
agent-pane.chat-width/standard	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/standard	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.chat-width/wide	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/wide	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.chat-width/wide-blocks	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/wide-blocks	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/short-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/short-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/wide-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/wide-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/no-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/no-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-floats/scrolled-to-end	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-floats/scrolled-to-end	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-floats/composer-grown	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-floats/composer-grown	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/shipped	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/shipped	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/two-thirds	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/two-thirds	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/half-tucked	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/half-tucked	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/before	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/before	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.copy-controls/output	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.copy-controls/output	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/new-chat	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/new-chat	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/after-turn	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/after-turn	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/working	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/working	Apple System Colors	unchanged	0%	own App.tsx

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

Passes: CI passes on 4a6266a623.

CI passes on 4a6266a623 (run 41215862832 attempt 1).

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.

web and size checks: green

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4122123816401 (2bace7350f)
• cmux NEXT nightly 1.0.0-nightly.4122185214701 (3531e040b6)
• cmux NEXT nightly 1.0.0-nightly.4122410931101 (5fb4ac7bc0)
• cmux NEXT nightly 1.0.0-nightly.4122444305401 (b3b2b165e9)

[blacksmith-sh]

Found 1 test failure on Blacksmith runners:

Failure

Test	View Logs
test_every_listed_hook_is_one_glaeda_released_with_the_check (main.SigningHooksInSt epWithGlaedaTests.test_every_listed_hook_is_one_glaeda_released_with_the_check)/ test_every_listed_hook_is_one_glaeda_released_with_the_check (main.SigningHooksInSt epWithGlaedaTests.test_every_listed_hook_is_one_glaeda_released_with_the_check)	View Logs

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

[teamleaderleo]

Owned by an agent session · session

[teamleaderleo]

Review (codex gpt-6-astra high, next-review): SHIP at abd00d3

No blocking findings.

Review coverage was limited by the omitted App.tsx snapshot and blocked repository reader; tests were not run.

[cmux-bot]

cmux-bot approves abd00d3: an independent review passed this exact head (next-review receipt by teamleaderleo). A push needs a new review; a later BLOCK at this head dismisses this approval.

[cursor]

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.

[teamleaderleo]

Review (codex gpt-6-astra high, next-review): BLOCK at 5e59e44

• [P2] webviews/src/agent-session/acpmux/conversation/foldAnchor.ts:74 — Collapsing long output can leave a blank viewport. Expand a long tool output near the transcript’s end, scroll down to “Show less,” then collapse it. This anchors the row’s now-offscreen top, while the new foldRoom preserves the old scroll offset. The collapsed content ends above the viewport, leaving blank space instead of visible transcript. trimmedFoldRoom retains that space even after the hold expires. Preserve a visible anchor or bound the retained room so collapsing cannot strand the reader below all content.

[teamleaderleo]

Review (codex gpt-6-astra high fast, review-router): SHIP at f24b1cd

• P3: webviews/src/agent-session/acpmux/conversation/dispatchCalls.ts:135: Removing the 2,000-character cap from outputSummary affects every dispatch kind, not just reports. A verbose plain-text briefs response now becomes an unbounded summary and accessible row label. Keep the uncapped behavior report-specific.

Visual: no after images were attached to this review (the body's media had not been posted); visual verdict to follow from the gallery run at this head.

[cursor]

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.

[cursor]

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.

[teamleaderleo]

Review (codex gpt-6.1-sol xhigh, next-review): SHIP at 798d36e

SHIP at 798d36e

Visual verdict: supplied before/after screenshots look clean; no clipping, bloated menu, or off-screen layout.

1. [P2] [follow-up] Highlighted code’s Wrap button (HighlightedCode.tsx:113-119) uses only aria-pressed, so it is missed by FOLD_TOGGLE (foldAnchor.ts:23-30). Wrapping code can change transcript height without anchoring the viewport.

2. [P2] [follow-up] The rendered-output Raw button (ToolOutputBody.tsx:128-133) has the same omission. Switching between Markdown and raw output can move rows while scrolled.

3. [P2] [follow-up] NESTED_CONTROL (foldAnchor.ts:33) omits [role="link"], while WriteLabel.tsx:93-100 places a custom role-link inside the newly buttonized tool row. Clicking that path is classified as a fold toggle and can briefly anchor or stop follow behavior.

Validation: targeted tests could not run because bun is unavailable in the review environment.

Follow-ups:

• [P2] [follow-up] Mark HighlightedCode’s Wrap control as a fold toggle.
• [P2] [follow-up] Mark ToolOutputBody’s Raw control as a fold toggle.
• [P2] [follow-up] Exclude custom role links from fold-toggle hit testing.

[cmux-bot]

cmux-bot approves 798d36e: an independent review passed this exact head (next-review receipt by teamleaderleo). A push needs a new review; a later BLOCK at this head dismisses this approval.

[teamleaderleo]

Review (codex gpt-6.1-sol xhigh, next-review): BLOCK at ee6c53d

BLOCK at ee6c53d

Visual verdict: compared all 17 supplied before/after pairs; no additional visual findings.

1. [P1] [blocking] foldAnchor.ts:72 — Collapsing long shell output can leave an empty transcript viewport. “Show less” now anchors the row’s top, which can be several screens above the viewport. Collapsing removes the visible output while foldRoom prevents the browser from clamping the offset, leaving all real content above the view. The blank space persists after the hold expires. Previously, the browser clamped to the remaining content. Hold the footer itself during collapse, as PromptText already does, or release excess room when the chosen anchor is offscreen.

Validation: changed TypeScript files parse; focused helper and report checks passed. Bun/browser tests could not run because the runtimes and dependencies are absent.

[teamleaderleo]

Review (codex gpt-6-astra high, next-review): SHIP at 4a6266a

SHIP at 4a6266a

Visual verdict: all supplied after screenshots match their before states; no layout regressions.

No findings.

Follow-ups: none

[teamleaderleo]

Review (gpt-6-astra high, router-review range 625b1ca..4a6266a): SHIP at 4a6266a. Earlier PR-form review (gpt-6.1-sol xhigh) gave SHIP at ee6c53d with images viewed; this head adds only the base merge with #28780 and its conflict resolution. cmux-ci at the merged head: typecheck, browser-lanes, fixed-waits and fmt clean; 613 unit and 53 transcript browser tests pass.

[cmux-bot]

cmux-bot approves 4a6266a: an independent review passed this exact head (next-review receipt by teamleaderleo). A push needs a new review; a later BLOCK at this head dismisses this approval.