fix(web): resolve hydration mismatch in dark mode toggle#80
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mattheliu wants to merge 1 commit intoshareAI-lab:mainfrom
Open
fix(web): resolve hydration mismatch in dark mode toggle#80mattheliu wants to merge 1 commit intoshareAI-lab:mainfrom
mattheliu wants to merge 1 commit intoshareAI-lab:mainfrom
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The dark state was initialized via `typeof window !== 'undefined'` branch inside useState, which returns different values on server (false) vs client (reads localStorage/matchMedia). This caused a React hydration error because the server-rendered Moon icon didn't match the client-rendered Sun icon. Fix: initialize useState with a static `false` and defer the real theme detection to a useEffect that runs after hydration. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
Headercomponent caused by dark mode state diverging between server and clientuseStateinitializer usedtypeof window !== 'undefined'branch which returnsfalseon server but may returntrueon client (vialocalStorage/matchMedia), causing SSR HTML (Moon icon) to mismatch client (Sun icon)useState(false)+useEffectto defer theme detection until after hydrationTest plan
cd web && npm run dev, open in browser with dark mode system preference🤖 Generated with Claude Code