No, if you want to protect the user's privacy, the source has to be your site, otherwise you're giving the CDN info about your customer. With the hash mechanism

No, if you want to protect the user's privacy, the source has to be your site, otherwise you're giving the CDN info about your customer. With the hash mechanism, 500 sites could share the same library, but only the site the user is visiting can ever know the user visited that site. Sure, one of those 500 gets the hit to performance on initial cache load, but averaged over all visitors to all sites, that's probably a comfortable trade. I think it would take Mozilla or Apple to push this. Google probably has too much skin in the CDN-info-gathering game.