[teamleaderleo]

Follow-up to #34464, from its review. Leo's ask there:

idk why names are ellipses'd so early plus the weird chevron spacing thing

#34464 took the 40%/45% caps off names and stopped them shrinking. That left a gap: in a narrow pane, a long name could push the chevron and the status off the row.

What changes

• A name still keeps its natural width while the message's first line has room to give.
• Once the first line is gone, the name is cut instead of the chevron or status. It does this with a flex-shrink of 0.0001: below a layout unit while the preview still has room, and all of the remaining overflow once the preview is gone.
• A received line's toggle never shrinks below the chevron's own room.
• A send's file name is cut with an ellipsis, the same way the preview is.
• The declined message line's chevron now uses the rows' 14/1.2, like every other row chevron.
• Left as they were: the Details and Raw toggles inside an opened card. They're in-card controls, not row disclosures, so they keep 12/1.4.

This is a restyle only. Nothing is removed or switched off.

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Fixes long agent names pushing the chevron and status off the message row in narrow panes.

• Names keep their natural width while the preview gives way first; once the preview is gone, the name is cut instead of the chevron or status.
• A received line's toggle gives way before its sender's name, shrinking down to the chevron's own room but never under it.
• A send's file name is ellipsized like the preview.
• The declined line's chevron now matches the rows' 14/1.2.

^{Written for commit 5daf62c. 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 5daf62c: 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=pr34509 -f ref=msg-rows-narrow-chevron -f platform=macos -f backend_mode=local

Gallery before/after for 5daf62c: 16 states rendered, 10 images differ, 1727 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 41754040420 -R manaflow-ai/cmux -n gallery-advisory-34509-5daf62c6bd34311c727c46a57d432995f0f44045 (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
agent-pane.access-offer/turn-no-credits	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-credits	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-low-credits	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-low-credits	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-offer	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-offer	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.activity-line-looks/none	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.activity-line-looks/none	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.activity-line-looks/spinner	Apple System Colors Light	changed	0.0562%	own conversation.css
agent-pane.activity-line-looks/spinner	Apple System Colors	changed	0.0483%	own conversation.css
agent-pane.activity-line-looks/kind	Apple System Colors Light	changed	0.0298%	own conversation.css
agent-pane.activity-line-looks/kind	Apple System Colors	changed	0.0231%	own conversation.css
agent-pane.activity-line-looks/aligned	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.activity-line-looks/aligned	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.addressed-message/relayed	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.addressed-message/relayed	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/unicode-boundary	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/unicode-boundary	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/lanes	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/lanes	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-subagents	Apple System Colors	changed	0.0492%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-subagents	Apple System Colors Light	changed	0.0489%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-hover	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-hover	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened	Apple System Colors	changed	0.0085%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened	Apple System Colors Light	changed	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened-long	Apple System Colors Light	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened-long	Apple System Colors	unchanged	0%	own AgentMessageRow.css
agent-pane.agent-message-row/outcomes	Apple System Colors	changed	0.0334%	own AgentMessageRow.css
agent-pane.agent-message-row/outcomes	Apple System Colors Light	changed	0.0333%	own AgentMessageRow.css

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

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4177134165301 (4a7517355a)
• cmux NEXT nightly 1.0.0-nightly.4177399658201 (443d56f95d)
• cmux NEXT nightly 1.0.0-nightly.4177479261801 (0df62819ad)

[teamleaderleo]

Review (subagent claude-opus-5-5, correctness): SHIP at 5daf62c
Checked that the received toggle shrinks first (1000 against the sender's 0.0001), its min-width keeps the chevron in view, and the sent and AgentMessageRow lines are unchanged.
Follow-ups: the later .cv-agentmsg__sentence > .cv-agentmsg__name rule overrides the opened row's 0 1 auto (an opened name can wrap only to the line).