The performance benefits of using the shared CDN copy of resources versus hosting your own with HTTP Keep-Alive are vastly overstated. In-theory, if everyone we

The performance benefits of using the shared CDN copy of resources versus hosting your own with HTTP Keep-Alive are vastly overstated. In-theory, if everyone were using the same version of the resources and everyone were using the same CDN, you'd see a benefit (maybe). In practice, there are too many variables and you end up cache missing most of the time, anyway. Besides, this was only ever a concern for bad devs loading tons of tracking scripts and hacking together sites via copy-paste anyway. If you're really concerned about performance, you should be building, tree-shaking, and minifying all of your JS into a single file.