Avoid double encoding in encode_shortcode_contents_callback

423c423
< 		$code = str_replace( array_keys($this->specialchars), array_values($this->specialchars), htmlspecialchars( $code ) );
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>                 $code = strtr( htmlspecialchars( $code, ENT_COMPAT | ENT_HTML401, 'UTF-8', false ), $this->specialchars );