v2.3.2 Improvement February 10, 2026

# Annotation panel performance

Annotation panel now renders 3x faster on specs with 200+ components. Virtualized list replaces full DOM render.

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The annotation panel on large specs was a known pain point. On specs with more than 200 components, the panel would freeze for 2–4 seconds on first open and scroll sluggishly after that. This release fixes it.

## What we changed

We replaced the full DOM render with a virtualized list using a windowing approach: only annotations currently in the viewport (plus a 150px buffer above and below) are rendered in the DOM. As you scroll, annotations are swapped in and out efficiently without layout thrash.

The result is a 3x improvement in initial render time on specs with 200+ components, and smooth 60fps scrolling on specs with up to 1,000 components in our testing.

## Benchmark

Spec size | Before (ms) | After (ms) | Improvement
--- | --- | --- | ---
50 components | 180 | 160 | ~11%
200 components | 1,840 | 610 | 67%
500 components | 4,200 | 820 | 81%

No settings changes are needed. The virtualized panel is the default for all users. If you notice any annotation rendering issues (particularly with annotations that rely on dynamic height), please file a support ticket with a spec link.

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