Older blog posts are missing the body on the new Drupal 8 site
It's still visible in full if you use d7.civicrm.org, e.g. https://d7.civicrm.org/blog/deepaksrivastava/civigmail-integration-with-gmail
Don't know if it was intentional to leave these out during the migration.
To upload designs, you'll need to enable LFS. More information