popup.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <title>War Content Filter</title>
    <link rel="stylesheet" href="popup.css" />
  </head>
  <body>
    <h1 id="popup_title"></h1>
    <p id="popup_description"></p>
    <div class="switch">
      <input type="checkbox" id="filtering-enabled" checked>
      <label for="filtering-enabled" id="popup_switch_label"></label>
    </div>
    <div class="whitelist">
      <h3 id="whitelist_title"></h3>
      <input type="text" id="whitelist_url" placeholder="Enter website URL" />
      <button id="whitelist_add_btn">Add to Whitelist</button>
    </div>
    <table id="whitelist-table"> <!-- Add the missing id attribute here -->
      <thead>
        <tr>
          <th id="website_label">Website</th>
          <th id="action_label">Action</th>
        </tr>
      </thead>
      <tbody>
        <!-- Table content will be generated dynamically -->
      </tbody>
    </table>
    <script src="popup.js"></script>
  </body>
</html>