我猜你的error.js没有捕捉和正确处理你的404错误。您的GlobalError组件只是记录useEffect()的错误。
我想您最好采用ErrorBoundary组件来成功地显示错误消息（在您的示例中，出现了错误！）

class ErrorBoundary extends React.Component {
  constructor(props) {
    super(props);
 
    // Define a state variable to track whether is an error or not
    this.state = { hasError: false };
  }
  static getDerivedStateFromError(error) {
    // Update state so the next render will show the fallback UI
 
    return { hasError: true };
  }
  componentDidCatch(error, errorInfo) {
    // You can use your own error logging service here
    console.log({ error, errorInfo });
  }
  render() {
    // Check if the error is thrown
    if (this.state.hasError) {
      // You can render any custom fallback UI
      return (
        <div>
          <h2>There was an error</h2>
          <button
            type="button"
            onClick={() => this.setState({ hasError: false })}
          >
            Try again?
          </button>
        </div>
      );
    }
 
    // Return children components in case of no error
 
    return this.props.children;
  }
}
 
export default ErrorBoundary;