Error: Minified React error #321 en el complemento de bloque personalizado de WordPress

Cada vez que escribo un useEffect() dentro de una función de componente de mi complemento de bloque, la página de edición se queda en blanco y la consola registra el mensaje:

react_devtools_backend.js:4026 Error: Minified React error #321; visit https://reactjs.org/docs/error-decoder.html?invariant=321 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at Object.it (react-dom.min.js?ver=17.0.1:9:43163)
at e.useState (react.min.js?ver=17.0.1:9:10899)
at Prompt (Prompt.js:5:35)
at N (element.min.js?ver=3dfdc75a0abf30f057df44e9a39abe5b:2:9552)
at U (element.min.js?ver=3dfdc75a0abf30f057df44e9a39abe5b:2:10502)
at N (element.min.js?ver=3dfdc75a0abf30f057df44e9a39abe5b:2:9284)
at lr (blocks.min.js?ver=658a51e7220626e26a92a46af5c2e489:3:111294)
at blocks.min.js?ver=658a51e7220626e26a92a46af5c2e489:3:137935
at xn (blocks.min.js?ver=658a51e7220626e26a92a46af5c2e489:3:138073)
at blocks.min.js?ver=658a51e7220626e26a92a46af5c2e489:3:139086

El componente:

import React, { useState, useEffect } from "react";
import axios from "axios";

function Prompt(props) {
  const [data, setData] = useState({ hits: [] });

  useEffect(() => {
    const fetchData = async () => {
      const result = await axios(
        "http://my-site-test.local/wp-json/wp/v2/posts?_fields[]=title"
      );

      setData(result.data);
    };

    fetchData();
  }, []);

  console.log(data);

  return (
    <>
      JSX...
    </>
  );
}

export default Prompt;

Traté de eliminar node_modules y reinstalar sin éxito…