A change introduced in Drupal 10 altered the way RSS feeds are generated. This change involved adding a tag nested within the element of each feed item. While seemingly minor, this change had unintended consequences. The issue has been fixed in Drupal 10.2.1.
RSS Feed
The term 'RSS' refers to Really Simple Syndication(Rich Site Summary). RSS allows you to group the content in your website and provides an easy way to view and share the contents in the site. RSS files are automatically updated whenever new content is published in the site. A user can subscribe to the RSS feed of a website using feed readers, such as Google, My Yahoo, Bloglines, Live Bookmarks etc. This keeps the user updated when new content has been added to the site. RSS is written as an XML file.