FrontendHaltBrowser internals·Intermediate·Conceptual·1 min read
What causes layout versus paint?
Short interview answer
Changing geometry-affecting properties can require layout and subsequent paint; visual-only changes can require paint; compositor-friendly changes may need only compositing. The affected region and engine optimizations determine actual cost.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.