Horizontal Rule in Post Return Blank using WordPress SEO Plugin

Reference: http://wordpress.org/support/topic/adding-horizontal-rule-in-post-return-blank

Whenever I add <hr /> tag anywhere inside post content, it returned blank post content due to WordPress SEO plugin activated on my different blogs.

Is there anyone else facing same problem?

Please let me know solution if possible.

http://wordpress.org/plugins/wordpress-seo/