Pause RAF offscreen
React chapter 136 · react-spring · visibility · source: pmndrs/react-spring · IntersectionObserver
The problem
A spring loop starts on mount and never stops. Scroll it out of view (or collapse the panel) and requestAnimationFrame still fires. Hidden carousels and offscreen toasts burn the main thread.
The pattern that fixes it
Observe the node. Run the frame graph only while intersecting (and the document is visible). react-spring pauses when the animated host is unmounted; production motion should also pause when it cannot be seen.
Keep learning
- Previous: Staggered springs
- Next: Render, then commit
- Related: Spring physics
- Related: RAF without React
- Related: Feature modules
- Related: Staggered springs
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