big tags formatted incorrectly in rss

[qdinar]

several (doubled, tripled) big tags formatted incorrectly in rss, may be single big tags behave same way

what is formatted

<blockquote><p><big><big>123</big></big></p>
<p><big><big>123</big></big></p></blockquote>

in normal view is formatted

<blockquote><p><big><big>123</big></big></p>
<p>123</p></blockquote>

in rss.

( and it is just

<blockquote><big><big>123
123</big></big></blockquote>

in editor)