为什么我不能在JavaScript中从cookie中解析超文本标记语言

// 存储HTML内容
localStorage.setItem('htmlContent', '<p>这是一个段落。</p>');

// 获取并解析HTML内容
const htmlContent = localStorage.getItem('htmlContent');
document.getElementById('targetElement').innerHTML = htmlContent;

// 打开数据库
const request = indexedDB.open('myDatabase', 1);

request.onupgradeneeded = function(event) {
  const db = event.target.result;
  const objectStore = db.createObjectStore('htmlStore', { keyPath: 'id' });
  objectStore.add({ id: 1, content: '<p>这是一个段落。</p>' });
};

request.onsuccess = function(event) {
  const db = event.target.result;
  const transaction = db.transaction(['htmlStore'], 'readonly');
  const objectStore = transaction.objectStore('htmlStore');
  const getRequest = objectStore.get(1);

  getRequest.onsuccess = function(event) {
    document.getElementById('targetElement').innerHTML = getRequest.result.content;
  };
};