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Pitfall — Cannot read properties of undefined (reading ‘title’)

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Error

  • Cannot read properties of undefined (reading ‘title’)

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Root cause

  • question was derived from FORM_SCHEMA instead of the runtime context, or qId is null/invalid.

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Fix

// derive qId from the snapshot, and fetch question via runtime const snap = React.useSyncExternalStore(rt.context.subscribe, rt.context.getSnapshot, rt.context.getSnapshot) const qId = snap.currentId ?? snap.firstUnansweredId ?? snap.eligibleIds[0] ?? null const question = qId ? rt.context.get.q(qId) : undefined // guard before reading properties return question ? : null