Files
livedash-node/.github/skills/vercel-react-best-practices/rules/rerender-transitions.md
Kaj Kowalski cd05fc8648 fix: resolve Prettier markdown code block parsing errors
- Fix syntax errors in skills markdown files (.github/skills, .opencode/skills)
- Change typescript to tsx for code blocks with JSX
- Replace ellipsis (...) in array examples with valid syntax
- Separate CSS from TypeScript into distinct code blocks
- Convert JavaScript object examples to valid JSON in docs
- Fix enum definitions with proper comma separation
2026-01-20 21:09:29 +01:00

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Markdown

---
title: Use Transitions for Non-Urgent Updates
impact: MEDIUM
impactDescription: maintains UI responsiveness
tags: rerender, transitions, startTransition, performance
---
## Use Transitions for Non-Urgent Updates
Mark frequent, non-urgent state updates as transitions to maintain UI responsiveness.
**Incorrect (blocks UI on every scroll):**
```tsx
function ScrollTracker() {
const [scrollY, setScrollY] = useState(0);
useEffect(() => {
const handler = () => setScrollY(window.scrollY);
window.addEventListener("scroll", handler, { passive: true });
return () => window.removeEventListener("scroll", handler);
}, []);
}
```
**Correct (non-blocking updates):**
```tsx
import { startTransition } from "react";
function ScrollTracker() {
const [scrollY, setScrollY] = useState(0);
useEffect(() => {
const handler = () => {
startTransition(() => setScrollY(window.scrollY));
};
window.addEventListener("scroll", handler, { passive: true });
return () => window.removeEventListener("scroll", handler);
}, []);
}
```