Clicks on island elements before hydration completes are captured
and replayed after boot finishes:
- shell.sx: inline script (capture phase) buffers clicks on
[data-sx-island] elements that aren't hydrated yet into window._sxQ
- boot.sx: after hydration + process-elements, replays buffered clicks
by calling target.click() on elements still connected to the DOM
This makes SSR islands feel interactive immediately — the user can
click a button while the SX kernel is still loading/hydrating, and
the action fires as soon as the handler is wired up.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>