[teamleaderleo]

Base-red-job: web / react-apps-check

webviews/test/message-preview-browser.test.ts fails on every recent base web run (41556018937, 41556254089, 41556613101, 41557134592, 41555236821 at 3891b41): line 70 expect(.cv-received count).toBe(2) gets 0, and line 138 (Minimal Mode) times out reading .cv-received__preview.

Cause: #32720 ("a turn's inbox notices and received lines are one 'Received N messages' row") deliberately gathers received messages next to each other into one "Received N messages" row whose messages show only once it opens. The agent-pane.message-preview stage has two received messages in a row, so they now sit inside that closed row. Green at 708aa6d, red from the run that includes #32720.

Fix: the test's open() opens the "Received N messages" row when the stage draws one, then reads each message's own line, toggle and preview inside it, the same way c6e52c4 handled the earlier fold. No product change; the behaviour is #32720's intended design.

Observed / Not run

• Read: the gallery fixture, Transcript: a turn's inbox notices and received lines are one "Received N messages" row #32720's projection (laneNoticeBatches.ts receivedRun) and its received-messages-columns-browser.test.ts selectors.
• The test runs in this PR's web CI; not run locally (lane VM).

Changelog

none

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Fixes the failing message-preview-browser.test.ts by opening the "Received N messages" row before reading message previews. #32720 groups consecutive received messages into one collapsible row that renders its messages only once opened, so the test now expands that row when the stage draws one and then reads each message's line, toggle, and preview inside it. No product change; the grouped row is #32720's intended behavior.

^{Written for commit 9592d2f. Summary will update on new commits.}

[github-actions]

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

Review 9592d2f: 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=pr32823 -f ref=lane/web-base-red-message-preview -f platform=macos -f backend_mode=local

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4156722095701 (26b4ff51c7)
• cmux NEXT nightly 1.0.0-nightly.4156852011001 (2f3ccfed7d)
• cmux NEXT nightly 1.0.0-nightly.4157013432001 (f338fc81fd)

[teamleaderleo]

Review (subagent opus-5.5 medium): SHIP at 9592d2f

Visual verdict: unchanged by this diff (test-only).

Checked: #32720 gathers the stage's two adjacent received messages into a closed "Received N messages" row (laneNoticeBatches.ts receivedRun); opening it restores two .cv-received rows with their own toggles, previews and panels; Minimal Mode batches the same way; code-first (one received) and sent-row tests are unaffected; formatting fits 120 columns.

Follow-ups: none.