twentythirteen theme issue with plugin

Hello guys!

I tested lot of plugins for minification and this is the best. Its invisible work is just great! Just great!

I am builidng theme right now and I want to recommend this plugin with it.

I have few issues with it, and I will describe it in separate topics.

I noticed that plugin have issue with new default wordpress theme, mainly with google font style which is added by
wp_enqueue_style( 'twentythirteen-fonts', twentythirteen_fonts_url(), array(), null );
and this function produce URL with such line
$fonts_url = add_query_arg( $query_args, "//fonts.googleapis.com/css" );

I have commented this out from my test page for now but you can see it on fresh WP install with plugin. It will report something like:

Request for https://demo4.csshover.pl//fonts.googleapis.com/css?family=Source+Sans+Pro%3A300%2C400%2C700%2C300italic%2C400italic%2C700italic%7CBitter%3A400%2C700&subset=latin%2Clatin-ext returned with HTTP 404 Not Found Try again

Hope it helps.

With regards.

https://www.ads-software.com/plugins/dependency-minification/