fix(desktop): consolidate prepend scroll correction#2855
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Wait for the virtualized timeline API before consuming initial channel positioning, and do not mistake measurement-driven offsets for reader input while the virtualizer is settling at the floor. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@sprout-oss.stage.blox.sqprod.co> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Replace the timeout-based bottom chase with explicit bottom intent driven by Virtua content and viewport geometry. Reader navigation, targeted messages, and history prepends still take ownership immediately, while late row reflow and composer typing no longer strand the timeline above its newest message. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@sprout-oss.stage.blox.sqprod.co> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Let Virtua own prepend measurement reconciliation by accumulating resize corrections from the live DOM offset. Retire that reconciliation on reader wheel input while preserving it for browser zoom, and remove the competing app-level semantic anchor watcher. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@sprout-oss.stage.blox.sqprod.co> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Keep bottom intent through zoom and ordinary row interactions, while retiring it for demonstrated timeline navigation and every virtualized target move. Cover mounted-target geometry races and listener ownership transitions. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@sprout-oss.stage.blox.sqprod.co> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Do not let completion of an older history request cancel a later jump-to-bottom command. Align smoke assertions with explicit reader ownership and the ResizeObserver-to-animation-frame settle boundary. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@sprout-oss.stage.blox.sqprod.co> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Programmatic scrollTop writes do not represent reader input. Dispatch an ordinary wheel event on the timeline before synthetic positioning so detached history tests exercise the production ownership contract. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@buzz.block.builderlab.xyz> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Use a dedicated Virtua store action to leave shift reconciliation when real wheel input takes ownership. Unlike ACTION_SCROLL_END, the transition does not idle scroll direction, clear frozen state, flush jumps, or emit the public scroll-end callback used by timeline retention. Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@buzz.block.builderlab.xyz> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@buzz.block.builderlab.xyz> Signed-off-by: Wes <wesbillman@users.noreply.github.com>
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## Summary - retire Virtua prepend reconciliation on every ordinary reader wheel event, including events suppressed from its separate wheel-timing heuristic - keep Ctrl+wheel browser zoom excluded from reader ownership - arm the Ctrl+wheel prepend probe before pagination begins so it cannot miss the commit - preserve ESM/CJS patch parity and update the patch lock hash ## Why main was red PR #2855 added the reader-wheel retirement action after Virtua's existing suppression guard. Once the first event set that guard, later events in the same wheel burst returned before retiring prepend mode. A late ResizeObserver correction could then pull the viewport backward by 20–40px. The same test had failed twice on #2855 but passed its final retry, so the PR job appeared green; the merge commit lost all three retries. The separate Ctrl+wheel failure was a test race: its MutationObserver was registered after the request had already been triggered and could miss the prepend commit. ## Validation - desktop full unit suite: 3,515 passed - pre-push desktop check: passed - `git diff --check`: passed - CI is the E2E verification; no local E2E was run Fixes the main-branch failure in CI run 30180099007. Signed-off-by: Wes <wesbillman@users.noreply.github.com> Co-authored-by: Carl <c7ebe626f000404285d3686e1dc74cc07cc60a9754a150041ba132e14bd3e2ec@buzz.block.builderlab.xyz>
johnmatthewtennant
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…unity-policy-fetch * origin/main: Fix formatting in README.md diagram (block#2284) fix(desktop): make Linux AppImage GStreamer work on non-Debian distros (block#2176) refactor(desktop): remove Agent directory section from Agents page (block#2290) fix(desktop): enable arboard Wayland backend so Linux copies reach the Wayland clipboard (block#2904) fix(desktop): supervise and re-arm relay-mesh runtime (block#2823) fix(agents): run live Databricks discovery instead of the fallback list (block#2890) fix(desktop): retire prepend mode on every reader wheel (block#2913) fix(desktop): consolidate prepend scroll correction (block#2855) docs(buzz-acp): correct agent key generation instructions (block#2875) fix(desktop): track concurrent agent turns up to the harness maximum (block#2882) docs(contributing): trim to goose-scale minimal intake surface (block#2780) fix(relay): preserve reconnect backoff (block#2759)
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Summary
scrollByloopWhy
Buzz admitted prepended rows using seeded estimates, then Virtua received multiple measurement corrections for the same transaction. Each correction was based on the same stale model offset, so a later write replaced an earlier correction instead of accumulating it. In the reproduced first page, that resurrected 452px of anchor drift; the app-level watcher merely corrected the lost virtualizer write afterward.
This fixes the correction inside Virtua and deletes the competing app writer, following the single-owner geometry invariant used by Berd rather than copying its spacer implementation.
Validation
git diff --checkcleanManual behavior
Load older history repeatedly while scrolling upward, then wheel downward during/after a prepend. The visible anchor should stay within the existing 5px contract during reconciliation, and deliberate reader movement should not be pulled back. Ctrl+wheel during the prepend commit must not cancel reconciliation.