Unwanted rerender in React.js

The code below generates a list of post titles. My intention is that when I click on a title, the list disappears and the post content is shown. What happens is that when I click on a title, the whole list appears again.

Here is the code:

import React, { useState, useEffect } from 'react';

function App() {
  const [posts, setPosts] = useState([]);
  const [showList, setShowList] = useState(true);

  useEffect(() => {
    .then(res => res.json())
    .then(data => setPosts(data));
  }, []);

  const onClickHandler = (id) => {
  return (
      {showList ? (
          <h1>List of posts</h1>
            {posts.map((post) => (
              <li key={post.id}>
                <a href="" onClick={() => onClickHandler(post.id)}>
      ) : (
        <h1>Post title</h1>

export default App;

When I run your code, after clicking on a post title, the list disappears. That is all I would expect it to do with the current code provided.

The list disappears and the page gets blank? Or the text “Post title” appears?

I tried this code on two browsers (Brave and Safari) and clicking on a link just rerenders the list.

… I found the error, the href attribute can’t be empty, if I use href="#" it works!