Streaming SSR

<section class="stage"><div class="heading">STREAMING <span class="hint">chunks arrive separately</span></div><div class="stream"><div class="pipeline"><span class="chunk">header</span><span class="chunk">article</span><span class="chunk">comments</span></div><div class="arrow">→</div><div class="rendered"><div class="piece">HEADER</div><div class="piece">ARTICLE</div><div class="piece">COMMENTS</div></div></div><div class="caption">The browser paints each available chunk</div></section>

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