JavaScript代码在Firefox正常运行，Chrome中无法生效的问题求助

我编写了一段用于上传JSON文件，对比Instagram关注者与被关注者列表，筛选出未回关用户的代码。该代码在Firefox中刷新页面后可将结果填充至textarea，但在Chrome中无法正常工作。我尝试通过onchange事件处理文件上传，仍未解决问题，恳请提供帮助。

代码实现 #

HTML部分 #

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Followers and Following List Comparison</title>
  <!-- <link rel="stylesheet" type="text/css" href="../styles.css" />  -->

</head>

<body>
  <div class="follows">
    <div class="followers">
      <h2>Upload Followers List</h2>
      <input id="followers" type="file" accept="application/json" />
      <textarea id="followers_result" rows=25 cols=50></textarea>
    </div>

    <div class="following">
      <h2>Upload Following List</h2>
      <input id="following" type="file" accept="application/json" />
      <textarea id="following_result" rows=25 cols=50></textarea>
    </div>

    <div class="result">
      <h2>People who are not following you</h2>
      <textarea id="result" rows=25 cols=50></textarea>
    </div>
  </div>
</body>

</html>

JavaScript部分 #

//followers list
document.getElementById('followers').onchange = function(evt) {
  try {
    let files = evt.target.files;
    if (!files.length) {
      alert('No file selected!');
      return;
    }
    let file = files[0];
    let reader = new FileReader();
    const self = this;
    reader.onload = (event) => {
      obj = JSON.parse(event.target.result);
      followers_data = Object.keys(obj).map(key => {
        return obj[key];
      });
      followers = followers_data.flat(1);

      follower_array = [];
      for (i = 0; i < followers.length; i++) {
        follower_array.push(followers[i].string_list_data[0].href);
      }
      document.getElementById('followers_result').value = follower_array.join("\n");
      followers = document.getElementById('followers_result').value;
    };
    reader.readAsText(file);
  } catch (err) {
    console.error(err);
  }
}

//following list
document.getElementById('following').onchange = function(evt) {
  try {
    let files = evt.target.files;
    if (!files.length) {
      alert('No file selected!');
      return;
    }
    let file = files[0];
    let reader = new FileReader();
    const self = this;
    reader.onload = (event) => {
      obj = JSON.parse(event.target.result);
      followers_data = Object.keys(obj).map(key => {
        return obj[key];
      });
      followers = followers_data.flat(1);

      follower_array = [];
      for (i = 0; i < followers.length; i++) {
        follower_array.push(followers[i].string_list_data[0].href);
      }
      document.getElementById('following_result').value = follower_array.join("\n");
      // console.log(document.getElementById('followers_result').value);
      following = document.getElementById('followers_result').value;


    };
    reader.readAsText(file);
  } catch (err) {
    console.error(err);
  }
}

following = document.getElementById('following_result').value;
console.log(following);
followingj = JSON.stringify(following);
spfollowing = JSON.parse(followingj);
finalfollowing = spfollowing.split('\n');
console.log(finalfollowing);

followers = document.getElementById('followers_result').value;
console.log(followers);
followersj = JSON.stringify(followers);
spfollowers = JSON.parse(followersj);
finalfollowers = spfollowers.split('\n');
console.log(finalfollowers);

finalfollowing = finalfollowing.filter(val => !finalfollowers.includes(val));
users = [];
finalfollowing.forEach(function(item) {
  user = item.split('https://www.instagram.com/');
  users.push(user[1]);
})

console.log(users);

内容的提问来源于stack exchange，提问作者Sarah