Wordpress: Add wmode to Wordpress embeds

gistfile1.php

// Fix embed wmode
    add_filter( 'embed_oembed_html', 'op_add_video_wmode', 10, 3);
    function op_add_video_wmode($html, $url, $attr) {
        if ( strpos( $html, "<embed src=" ) !== false ) {
            return str_replace('</param><embed', '</param><param name="wmode" value="opaque"></param><embed wmode="opaque" ', $html); 
        } elseif ( strpos ( $html, 'feature=oembed' ) !== false ) {
            return str_replace( 'feature=oembed', 'feature=oembed&wmode=opaque', $html );
        } else { 
            return $html;
        }
    }