[teamleaderleo]

Carries #28139 (its owner lane went idle about six hours ago mid-step; all of its commits are kept with their authorship) onto current feat-cmux-next.

Leo, verbatim, 2026-10-30: “i still dont see the hover previews being like rex with multiple tabs being clickable”

Earlier asks this answers, verbatim: “and also why dont we have the rex thing yet of being abel to access the individual tabs in a workspace on its hover preview the best of both worlds thing” and (2026-10-24) “default just only show the inner tabs on hover and be able to go to and focus them when hovering ovre workspaces … wouldnt first prompt/input needing/whatever MAYBE be nice...? idk tho. we can tuck that behind toggle”.

Change

A workspace's hover preview in the sidebar lists that workspace's tabs, and each one is a click away: clicking a tab row focuses that workspace and that tab. The card opens tabs-first; status, prompts, history, usage and custom content stay available behind one "Show details" toggle. Overflowing tabs expand inside the same bounded scroll area with "Show more". Arrow keys move through tabs only while the pointer is on the card; keys on the workspace row still go to the focused terminal. Spec: leo-workspace design/sidebar.md (Hover previews; the tab list was listed there as cmux#24785, which this carries).

Carry work on top of #28139: merged feat-cmux-next; the conflicts were in HoverCardBody/HoverCardCoordinator (base added cornerRadius, this PR added interactive; both kept and passed through to HoverCardPanel.present) and plans/cmux-next/sidebar-owner.md (both sections kept).

Screenshots

Fleet captures (2x, cmux-mac-mini via capture-host, the hover-card gallery's synthetic data), cropped to the card. Before is base b93dcfbc826d, after is this head.

	Before (base)	After (this PR)
Light
Dark

Before, the card had no tabs at all: status, facts, PR and resources only. After, the chosen default opens tabs-first; each row is one tab (kind icon, name, folder, its status dot or spinner) and clicking it focuses that tab. "Show 3 more" expands the list in place; "Show details" brings back the status, facts, PR and resources.

The full gallery, with the three other placements we compared (tabs after status, tabs below title with details open, compact tabs below details): light, dark.

I viewed the after images (both crops and the full gallery, light and dark) before marking this ready. pr-media upload through cmux-ci capture --pr failed from this agent host (glaeda's broker refuses the contents API read, #28265), so the images went up with scripts/pr-media.py directly.

Validation

Pending at the head: fleet app compile, the hover-card suites (WorkspaceTabHoverCardTests and the nine adapted hover suites), independent review.

Risk: hover-card event routing. The card now takes mouse events, so the focused terminal must keep its keys while the pointer rests on the workspace row (covered by WorkspaceTabHoverCardTests).

Size: about 1,250 lines, most of it the 21-locale strings for the details toggle and the regression tests; the list, its click routing and the toggle are one interaction and don't land usefully apart.

Agent session: agent session

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[github-actions]

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

Review f86a6ae: 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=pr28897 -f ref=carry/28139-hover-tabs -f platform=macos -f backend_mode=local

Default changes

This pull request changes 3 defaults at f86a6aea2d52 (what everyone gets without configuring anything):

• tunable-source.CmuxNextApp/Focus/DebugFocus.swift:window: "87ee3e2e0cec4980a2829d1e2474a3df7dc797b9bd8e768ca1f88ee38c00abb0" -> "b805a4c2b00844e7b2f0cb641f67940566dffb1e89e4aab687211bc6e25ffc3b"
• tunable-source.CmuxNextApp/InputVerification/DebugMouse.swift:hoverCard: (none) -> "7175b7af653eecf98cab75e2650a10cd6b7449ab26c3c67bb1e3bc7688633a30"
• tunable-source.CmuxNextApp/InputVerification/DebugMouse.swift:send: "109678464546150433b22506d4a396faaeefc8780735a38a07897e61c9bace43" -> "3b90069867380238edfa0db55dd00eb317e7688c6019d7ca37340f1f6c11adf0"

Signed off on this commit by review (codex, router-review).

Merge receipt: merged as c3a355cd57b9 with these defaults changed, signed off by review (codex, router-review).

Regenerate the snapshot with python3 scripts/ci/defaults_guard.py snapshot.

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4120428201901 (e1849d914e)
• cmux NEXT nightly 1.0.0-nightly.4120480532201 (6b2795d84a)

[teamleaderleo]

Review (codex, router-review): SHIP at a0430b2

Reviewer: codex gpt-6-astra high, fast tier.

Follow-ups: 2. Each lands as an issue in this repo that links this receipt; the lane that opened the PR fixes it forward.

SHIP at a0430b2

Visual verdict: Both supplied after screenshots pass in light and dark; no visible clipping or excessive controls.

1. [P2] [follow-up] WorkspaceTabHoverCard.swift:155: Clicking the overflow scrollbar dismisses the card. The mouse allowlist accepts rows and “Show more,” but excludes NSScroller, so the coordinator treats a scrollbar press as dismissal. Accept the scrollbar so users can drag through expanded tabs.

2. [P2] [follow-up] WorkspaceHoverCard.swift:146: “Hide details” does not persist on a card opened through “Show Resource Usage.” detailsRequested remains set until dismissal, so the next content refresh—or clicking “Show more”—reopens details and restarts sampling. Consume the request after initially expanding the card.

AppKit tests could not run on this Linux host. The changed localization and tour JSON files parse successfully.

Follow-ups:

• Accept scrollbar clicks without dismissing the card.
• Consume the resource-details request after its initial expansion.

[teamleaderleo]

Review (codex gpt-6-astra high, router-review): BLOCK at 713358d

BLOCK at 713358d

Visual verdict: after images show the intended compact tabs-first card; no visual blocker.

1. [P1][blocking] HoverCardCoordinator.handleMonitoredEvent only preserves interactive clicks for leftMouseDown (Packages/macOS/CmuxNext/Sources/CmuxNextDesign/HoverCards/HoverCardCoordinator.swift:395-401). The matching leftMouseUp falls through to dismiss(.click) at lines 412-417, so clicking “Show details” or “Show more” immediately starts dismissing the card and clears their callbacks. These controls therefore cannot expand the card in place as specified.

[teamleaderleo]

On the BLOCK at 713358d (#28897 (comment)): the card's event monitor never sees a mouse-up. Its mask is [.keyDown, .leftMouseDown, .rightMouseDown, .otherMouseDown, .scrollWheel] (HoverCardCoordinator.updateMonitor), so a leftMouseUp cannot reach handleMonitoredEvent's dismiss. An accepted press goes to the control, and NSButton takes its own release in its tracking loop.

f86a6ae names that mask HoverCardCoordinator.monitoredEvents and adds WorkspaceHoverCardScrollTests.pressingShowDetailsKeepsTheCardAndItsReleaseIsNeverMonitored. The test checks that the mask has no .leftMouseUp, that a press on Show details is passed through and the card stays, and that the click then expands the card in place. It passed on the fleet at f86a6ae (WorkspaceHoverCardScrollTests 4/4, along with WorkspaceTabHoverCardTests 16/16 and four other hover suites).

[teamleaderleo]

Review (codex, router-review): SHIP at f86a6ae

Reviewer: codex gpt-6-astra high, fast tier.

Follow-ups: 2. Each lands as an issue in this repo that links this receipt; the lane that opened the PR fixes it forward.

SHIP at f86a6ae

Visual verdict: Both light and dark after screenshots are readable, with no visible clipping or redundant controls.

1. [P2] [follow-up] WorkspaceTabHoverCard.swift:155 — Dragging the overflow scrollbar dismisses the card. After “Show more,” clicking the scrollbar hits ThinScroller, but the allowlist accepts only tab rows and the more button. The coordinator therefore dismisses the card on mouse-down. Accept scrollbar interaction so users can drag through overflow tabs.

2. [P2] [follow-up] WorkspaceHoverCard.swift:146 — Collapsed details reopen after a resource-card refresh. Open “Show Resource Usage,” click “Hide details,” then click “Show more.” Its refresh rebuilds the body, and the retained detailsRequested flag expands details and restarts sampling. Workspace updates trigger the same behavior. Consume the request after its initial expansion.

AppKit tests could not run in this Linux box. The changed JSON files parse successfully.

Follow-ups:

• Accept overflow scrollbar clicks without dismissing the card.
• Consume the initial details request so subsequent refreshes preserve the user’s collapse choice.