Frontend & browser·Rendering and the browser pipeline
the page is interactive on arrival because no framework code re-ran to make it so.
Resumability
An alternative to hydration where the server serialises enough state into the HTML that the client can pick up mid-execution rather than replaying the render. Event handlers are attached lazily, on the first interaction, so the startup cost is close to zero regardless of page size. The trade is a larger HTML payload and a much less common execution model, which shows up as tooling and debugging friction.