SideChat transcript: every 2s poll rebuilt ALL row objects, so every
row (markdown parse + DOMPurify included) re-rendered even when the
log had not changed. transcriptRows now takes the previous poll's
rows and re-adopts the position-aligned rows whose content is
identical (reuseRows) — only the changed tail rebuilds. The view
feeds the memoized array back through a ref; unit tests pin the
identity contract (unchanged rows keep object identity, changed rows
and everything past the change rebuild, tool-result landings never
re-adopt).
FileTree: expanded/revealed membership was an includes() scan per
rendered row (O(rows × expanded) per render on deep trees); one Set
per render keeps it O(1) per row.
Shell: buildNewTabOptions was inlined in the two Workbench JSX
sites — two fresh arrays per render (drag state, resizes) re-rendered
every LeafView's + affordance. One shared memo now.
DiffPane resize / TerminalView ResizeObserver: pointer and resize
streams fired a setState / glyph-measuring fit() per event; both ride
per-frame batching now (frame-batcher in the core, a local rAF gate
in the lazy terminal chunk). SessionLens sizes each row's content
with a Blob (a UTF-8 encode of the whole edit) — that moved from
per-row-per-render into one memoized pass per changed fold.
Boot: loadPrefs and loadExternalDisable each fetched the settings
document, serially, before the first paint — and the second had no
timeout, so a stalled wire kept the sidebar unmounted forever. Both
decisions now ride ONE fetch (loadBootDecision) under the existing
2s race.
GitLens: the 2s silent poll re-listed worktrees on every tick (a
second git process per tick for a list that almost never changes, and
a fresh worktrees array re-render each time). Silent ticks now fetch
only the selected checkout's status; every 15th tick (~30s) re-lists
and re-runs auto-selection, so an agent-created linked checkout is
still picked up mid-session.
ChangesTab: extractFileOps parses every accumulated tool/call (up to
4000 events); the poll ran it once for the badge and the render ran
it AGAIN per tick, and the fresh array defeated the downstream memo.
The fold now runs once per poll and its result rides a ref shared by
badge and render (reset on session switch).
Menghuan1918