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//* Defer parsing of JavaScripts
function defer_parsing_of_js ( $url ) {
	if ( FALSE === strpos( $url, '.js' ) ) return $url;
	if ( strpos( $url, 'jquery.js' ) ) return $url;
	return "$url' defer='defer";
}
add_filter( 'clean_url', 'defer_parsing_of_js', 11, 1 );

//* Defer parsing of JavaScripts, but exclude OptinMonster!
function defer_parsing_of_js ( $url ) {
	if ( FALSE === strpos( $url, '.js' ) ) return $url;
	if ( strpos( $url, 'jquery.js' ) || strpos( $url, 'optinmonster' ) ) return $url;
	return "$url' defer='defer";
}
add_filter( 'clean_url', 'defer_parsing_of_js', 11, 1 );