Code Quiz

useFocusEffect Re-run Bug

Spot why this screen-focus effect fires on every render instead of only on focus.

Codejavascript

import { useFocusEffect } from '@react-navigation/native';

function ProfileScreen() {
  useFocusEffect(() => {
    const sub = api.subscribeToUpdates();
    console.log('screen focused');
    return () => sub.unsubscribe();
  });

  return <ProfileView />;
}

What is the bug in this useFocusEffect usage?

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