User blog comment:DaNASCAT/Update Your CSS and JavaScript To Speed Up Your Wiki/@comment-4674838-20120823031400/@comment-3508190-20120823044836

I haven't been able to test this feature (see above), but from reading the function declaration of  I'd say it simply creates a specially formed URL. That URL will work in a CSS @import statement as well. I don't know exactly what the URL looks like at this point, but I can tell you with absolute certainty that you will be able to create this URL by hand - i.e. without using !