[Plugin: WP Super Cache] Speedymirror origin pull?

I am trying out wp-super-cache instead of W3 Total Cache but I am not sure about the CDN part. On W3TC I had it running with speedymirror so all images always were pulled from the CDN automatically.

But do I need to do some sync outside wp-super-cache for the wp-content, wp-includes content to be put on the CDN? Is this not done on the fly?

https://www.ads-software.com/extend/plugins/wp-super-cache/