fix(desktop): keep transcript auto-scroll pinned through stream end - #8291
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…sengine#8269) Long answers (>=8k chars) render their final blocks through an async markdown worker after the stream settles. Nothing repinned after that layout growth: the streaming auto-scroll effect only runs on live token changes, and the virtualizer's anchor compensation keeps the anchor row in place instead of following the tail - then the bottom-state re-evaluation (distance >= threshold) flips the transcript to manual mode, permanently disabling auto-scroll until the user scrolls again. Two coordinated fixes: 1. While pinned (tail-follow), the virtualizer no longer compensates scroll position on row-size changes (shouldAdjustScrollOnItemSizeChange returns false when pinned). Every measured row-size change while pinned is instead folded into the existing frame-batched repin (measureElement wrapper -> scheduleRepinIfWasPinned with a new "row-size" scroll owner), so tail growth, async worker swaps and image loads all keep the viewport at the bottom. 2. Stream-end fallback: when the live snapshot settles (turn_done) and the transcript is still pinned, scrollToBottomAfterLayout waits a few frames for the synchronous markdown layout and snaps to the bottom. A user who scrolled away during the stream is never yanked back. Tests: 20 assertions on the new pure arbitration functions (shouldAdjustScrollOnItemSizeChange, shouldRunStreamEndRepin, row-size owner permission); existing scroll-manager tests still pass; tsc --noEmit and eslint clean. Cache-impact: none - frontend-only rendering/scroll behavior Cache-guard: none System-prompt-review: none - no prompt, config schema, memory, output style, or skill behavior changes Documentation-impact: none - fixes existing transcript scroll behavior; no CLI or user-facing docs change
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Problem: - Nested downward handoff at the physical bottom detached streaming tail-follow. - Passive tail writes rejected during an active gesture were dropped, so final token and row-size growth could leave the viewport behind. Root cause: - Nested handoff discarded wheel direction and always released auto-scroll. - Gesture arbitration had no generation-aware replay for blocked passive owners. Fix: - Propagate normalized nested deltas and release only for upward or detached reading intent. - Replay blocked stream, resize, footer, and row-size repins once after gesture idle using the current scrollHeight. - Cancel deferred work on manual intent, selection, explicit navigation, and tab generation changes. - Adapt esengine#8291's row-size ownership, pinned measurement rule, and stream-end fallback into the unified gesture controller. - Add deterministic and real Chromium regression coverage. Verification: - pnpm test:transcript - pnpm test:transcript-browser - pnpm test:typecheck - pnpm test:motion - pnpm build - go run ./tools/repolint Co-authored-by: LI Xinyu <Lxy1962@bupt.edu.cn>
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…8264) * fix(desktop): stop trackpad scroll stalls in the chat transcript Problem: On macOS, two-finger scrolling the chat content area felt sticky and jumpy—especially over markdown tables—because nested overflow containers latched the trackpad and virtualizer/stream rewrites fought native inertia mid-gesture. Root cause: CSS overflow-x:auto promotes overflow-y to auto, so ordinary tables/code blocks became vertical scroll ports; virtualizer height compensation and stream tail-follow could still write scrollTop while the user was gesturing. Fix: Add a short user-gesture lock that blocks compensating scroll writes, promote edge/non-scrollable nested wheels to the transcript with latching handoff, keep small tables and code blocks out of nested vertical scroll, and mark large virtual tables for handoff. Verification: npx tsx scroll-manager, transcript-scroll-session, nested-scroll-handoff, markdown-table-virtual, typography-overflow-contract, and transcript-virtualization tests. * fix(desktop): fold large tables and idle-remeasure after scroll Problem: Large markdown tables still introduced nested vertical scroll ports by default, and virtualizer remeasure could jump after a trackpad gesture settled. Root cause: Oversized tables mounted a max-height virtual scroller immediately, and height compensation was deferred only mid-gesture, not batched once after the hold window. Fix: Collapse tables above the virtual threshold to a 12-row document-flow preview with Expand all / Collapse; expanded tables keep the nested virtual scroller with handoff. After gesture idle, measure once and reconcile the reading anchor. Verification: npx tsx markdown-table-virtual, scroll-manager, transcript-scroll-session, and nested-scroll-handoff tests. * fix(desktop): stabilize native transcript scrolling Problem: Long variable-height transcripts could stall or jump while trackpad inertia, native scrollbar input, or Windows middle-button auto-scroll overlapped virtualizer and resize compensation. Creation scrollbar sensitivity could also change while rows mounted. Root cause: Scroll ownership only covered wheel, touch, and keyboard intent; treated unowned native scroll events ambiguously; remeasured the entire virtualizer after every idle gesture; and recomputed custom-scrollbar geometry during a drag. A stale scrollend could also settle a newer gesture. Fix: Model native input sessions explicitly, arbitrate controller-owned scroll events, normalize wheel delta modes, guard stale scrollend, freeze custom-scrollbar drag geometry, and measure only real layout invalidations with anchor reconciliation. Split interaction and scrollbar concerns out of Transcript and add real-browser stability coverage. Verification: - pnpm --dir desktop/frontend test:transcript - pnpm --dir desktop/frontend test:transcript-browser - pnpm --dir desktop/frontend typecheck - pnpm --dir desktop/frontend test:typecheck - pnpm --dir desktop/frontend test:motion - pnpm --dir desktop/frontend build - go run ./tools/repolint * fix(desktop): latch manual transcript scroll intent Problem: A short upward wheel, trackpad, native scrollbar, or Creation scrollbar movement could remain inside the 80px near-bottom band. After the gesture quiet window, streaming output could therefore re-enable tail-follow and pull the viewport back down. Root cause: The scroll manager treated geometric proximity as user intent and recomputed stick mode from the near-bottom threshold after every native scroll event. Fix: Latch explicit user detachment across gesture settlement, keep resize and stream repins disabled while detached, and restore tail-follow only at the physical bottom or through an explicit bottom/reset action. Apply the same contract to the Creation scrollbar. Verification: - pnpm --dir desktop/frontend test:transcript - pnpm --dir desktop/frontend test:transcript-browser - pnpm --dir desktop/frontend test:typecheck - pnpm --dir desktop/frontend test:motion - pnpm --dir desktop/frontend build - go run ./tools/repolint * fix(desktop): preserve tail follow across scroll ownership Problem: - Nested downward handoff at the physical bottom detached streaming tail-follow. - Passive tail writes rejected during an active gesture were dropped, so final token and row-size growth could leave the viewport behind. Root cause: - Nested handoff discarded wheel direction and always released auto-scroll. - Gesture arbitration had no generation-aware replay for blocked passive owners. Fix: - Propagate normalized nested deltas and release only for upward or detached reading intent. - Replay blocked stream, resize, footer, and row-size repins once after gesture idle using the current scrollHeight. - Cancel deferred work on manual intent, selection, explicit navigation, and tab generation changes. - Adapt #8291's row-size ownership, pinned measurement rule, and stream-end fallback into the unified gesture controller. - Add deterministic and real Chromium regression coverage. Verification: - pnpm test:transcript - pnpm test:transcript-browser - pnpm test:typecheck - pnpm test:motion - pnpm build - go run ./tools/repolint Co-authored-by: LI Xinyu <Lxy1962@bupt.edu.cn> --------- Co-authored-by: LI Xinyu <Lxy1962@bupt.edu.cn>
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Problem
Fixes the transcript auto-scroll failure reported for long answers. Answer text ≥8000 chars (STREAMING_TAIL_THRESHOLD) renders its final blocks through an async markdown worker after the stream settles (
MarkdownHistory.tsx→ worker parse). Nothing repins after that layout growth:Transcript.tsx) only runs on live token changes — afterturn_doneclears the live snapshot it never fires again.anchorTo: "end"+shouldAdjustScrollPositionOnItemSizeChange) keeps the anchor row in place instead of following the tail.useScrollManager.updateBottomState) sees distance ≥ 80px, flips the transcript tomanualmode, and permanently disables auto-scroll — the viewport is stuck mid-transcript with only the jump-to-bottom button as an escape.Fix
Two coordinated changes:
Pinned rows never go through anchor compensation. New pure rule
shouldAdjustScrollOnItemSizeChange(pinned, mode): while pinned (tail-follow) the virtualizer does not compensate on row-size changes. Every measured row-size change while pinned is instead folded into the existing frame-batched repin — themeasureElementwrapper callsscheduleRepinIfWasPinnedwith a new"row-size"scroll owner — so tail growth, async worker swaps and image loads all keep the viewport at the bottom.Stream-end fallback repin. When the live snapshot settles (
turn_done) and the transcript is still pinned,scrollToBottomAfterLayout(3)waits a few frames for synchronous markdown layout and snaps to the bottom. A user who scrolled away during the stream (shouldRunStreamEndRepingates on pinned) is never yanked back.Tests
shouldAdjustScrollOnItemSizeChange(all mode×pinned quadrants incl. selection modes),shouldRunStreamEndRepin(repin only on live→absent while pinned), andcanTranscriptScrollOwnerWrite("row-size", …)permissions.scroll-manager.test.tsxsuite still passes (17 assertions).tsc --noEmitand eslint clean.Cache-impact: none - frontend-only rendering/scroll behavior
Cache-guard: none
System-prompt-review: none - no prompt, config schema, memory, output style, or skill behavior changes
Documentation-impact: none - fixes existing transcript scroll behavior; no CLI, docs or config surface changed