Message actions still fade in on hover and focus, but their row now keeps a stable height so transcript content does not jump when the pointer enters or leaves a message.
Constraint: Preserve the existing hover-only visibility and copy/fork interaction model.
Rejected: Keep animating height from zero | it causes the visible transcript reflow this change is fixing.
Confidence: high
Scope-risk: narrow
Tested: cd desktop && /Users/nanmi/.cache/codex-runtimes/codex-primary-runtime/dependencies/node/bin/node ./node_modules/typescript/bin/tsc --noEmit
Tested: git diff --check -- desktop/src/components/chat/MessageActionBar.tsx desktop/src/components/chat/MessageList.test.tsx
Not-tested: Focused Vitest could not complete in this local shell because the Vitest/esbuild startup process stalled or reported esbuild service stopped.
The previous fix moved the hover group onto the message shell, but the action row still occupied layout space while invisible. That invisible row kept expanding the shell hit area, so moving the pointer into the empty metadata strip could still reveal copy and timestamp controls.
Collapse the action row to zero height by default and expand it only while the message shell is hovered or focused. Keep message content spacing separate from the action row so hidden controls do not create a hover target.
Constraint: Copy/fork controls must remain reachable after the bubble reveals them.
Rejected: Use display:none for the action row | would remove the keyboard focus path entirely.
Confidence: high
Scope-risk: narrow
Directive: Keep hidden message metadata rows out of normal hover hit-testing; do not reintroduce invisible layout space around chat bubbles.
Tested: cd desktop && bun run test src/components/chat/MessageList.test.tsx --run -t "keeps user actions anchored"
Tested: cd desktop && bun run test src/components/chat/MessageList.test.tsx --run
Tested: cd desktop && bun run test src/components/chat/UserMessage.test.tsx --run
Tested: bun run check:desktop
Tested: git diff --check
Not-tested: Live Tauri native hover smoke
Related: #642
Message action controls stay visible through focus-within for keyboard navigation, but pointer clicks left the copy/fork buttons focused after the mouse moved away. Release pointer focus on message actions so hover controls return to their quiet state while keeping Tab focus behavior intact.
Constraint: Message actions use focus-within for keyboard accessibility and should not remove that path.
Rejected: Remove focus-within reveal | would regress keyboard users who tab to copy or fork.
Confidence: high
Scope-risk: narrow
Directive: Keep pointer-only blur scoped to message action controls; do not remove focus-within without a replacement keyboard affordance.
Tested: cd desktop && bun run test src/components/chat/MessageList.test.tsx --run
Tested: bun run check:desktop
Not-tested: Live Tauri manual hover smoke
Related: #642
Message rows should stay visually quiet until the user needs copy or fork controls. The action row now appears on message hover/focus, uses icon-sized controls, and shows the message timestamp beside the actions with locale-aware recent and historical formats.
Constraint: Desktop chat actions already own copy and fork affordances, so the change keeps that surface instead of adding a separate always-visible timestamp row.
Rejected: Keep text-labeled Copy buttons | the row remained too visually heavy for every message.
Confidence: high
Scope-risk: narrow
Directive: Keep copy, fork, and timestamp as one hover/focus metadata row unless the message layout is redesigned as a whole.
Tested: bun run check:desktop
Not-tested: Live Tauri native packaging
Desktop transcript messages already expose copy controls in the shared action row. The fork affordance was rendered as its own zero-height hover row, which left the icon below Copy and made the action feel detached from the message toolbar. Moving the fork button into the existing action bar keeps the controls aligned while preserving the original branch-session API path.
Constraint: Desktop message actions should stay visually grouped for both user and assistant messages
Rejected: Keep a separate fork-only hover row | it reproduces the two-line layout regression shown in the desktop UI
Confidence: high
Scope-risk: narrow
Directive: Keep future per-message actions inside MessageActionBar unless they need a different interaction surface
Tested: cd desktop && bun run test src/components/chat/MessageList.test.tsx --pool forks --poolOptions.forks.singleFork=true
Tested: cd desktop && bun run test src/i18n/index.test.tsx --pool forks --poolOptions.forks.singleFork=true
Tested: cd desktop && bun run lint
Tested: bun run check:desktop
Not-tested: Full live desktop backend fork-click E2E
The chat surface now relies on the current-turn changes card for file rollback, so the older per-message hover rewind affordance was removed to avoid two competing rollback models.
Constraint: Current-turn undo still depends on the existing checkpoint rewind API.
Rejected: Keep both rewind entry points | duplicate rollback affordances make the product harder to explain and test.
Confidence: high
Scope-risk: moderate
Directive: Prefer adding rollback behavior through the current-turn change card instead of restoring per-message hover rewind.
Tested: bun test src/server/__tests__/sessions.test.ts
Tested: cd desktop && bun run test
Tested: cd desktop && bun run lint
Tested: cd desktop && bun run build
Not-tested: Browser E2E scripts were updated but not executed in this commit.
Two desktop surfaces regressed in ways that made the app harder to read and operate.
The plugin header compressed summary cards and action buttons too early for the available width,
and the rewind/copied affordances in chat were sharing the same horizontal lane as message bubbles,
which visually broke the expected "user on the right, assistant on the left" transcript structure.
This commit keeps both fixes narrow: the plugin header now delays its split layout and lets summary
cards and controls reflow responsively, while chat message actions live inside each message column so
interaction affordances no longer distort the bubble alignment.
Constraint: Desktop settings and transcript layouts must remain readable in narrower window widths
Rejected: Keep message actions inline with the bubble row | action buttons keep stretching the message lane and blur role alignment
Rejected: Hide rewind and copy entirely until a larger redesign | removes the control instead of fixing the regression
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep transcript actions inside the message column unless a future redesign also redefines bubble alignment rules
Tested: bun run test src/__tests__/pluginsSettings.test.tsx --run; bun run test src/components/chat/MessageList.test.tsx --run; bun run lint; bun run build; agent-browser verification against local mock desktop session
Not-tested: Real Tauri runtime screenshot on a live backend session after these layout changes
The desktop client already had a conversation-level rewind UI concept on the
CLI side, but the web/desktop surface lacked the protocol, session trimming,
and file checkpoint restore path needed to make rewind trustworthy. This change
adds a desktop-specific rewind API, wires the message-level UI affordance and
confirmation modal, enables SDK file checkpointing for desktop sessions, and
covers the restore path with service tests plus a real agent-browser workflow.
Constraint: Desktop sessions run the CLI in SDK/print mode, so file checkpointing had to be enabled explicitly for that path
Constraint: main branch is checked out in a separate worktree, so merge-back must happen from the primary worktree after commit
Rejected: UI-only rewind that only trims local state | would leave persisted transcript and disk state inconsistent after refresh
Rejected: Reuse getLastSessionLog as the sole snapshot source | active rewind must read file-history metadata directly from the session file
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Keep desktop rewind keyed to persisted user-message order unless the UI model starts carrying stable transcript UUIDs end-to-end
Tested: bun test src/server/__tests__/conversation-service.test.ts src/server/__tests__/sessions.test.ts; desktop MessageList vitest; desktop tsc no-emit; live agent-browser E2E on isolated ports with file edit then rewind
Not-tested: Browser E2E matrix for multi-file and second-edit scenarios is still covered at service-test level rather than full UI level
Move the Copy button from always-visible below messages to the
bottom-right side of each message bubble, only appearing on hover.
Reduces visual clutter in chat conversations.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The session view exposed copy affordances in a way that implied the
whole conversation would be copied, while user prompts had no copy
path at all. This changes copy to a per-message footer action so the
scope is explicit for both prompts and assistant replies, and reuses
the shared clipboard helper instead of maintaining a second copy path.
Constraint: The worktree contains unrelated in-progress changes that must stay uncommitted
Rejected: Keep a floating action above each message | it interrupted reading order and still looked session-scoped
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep copy affordances attached to individual message blocks so the copied scope stays obvious
Tested: bun run test src/components/chat/MessageList.test.tsx; bun run lint
Not-tested: Manual desktop visual QA across dense multi-message sessions
