I've run into 3 different instances of this, all running 2.0 RC3. When I put a
<hr> tag into the body of a post, or page, then try to put a
tag after it, it doesn't work. It will 'look' right in the source, and right in the html editor, but when I save it, it strips the
tag out (along with the closing tag) in the actual post. When I remove the
<hr> tag, it works fine and leaves the tag where it is.
<br> and other tags don't seem to be affected.