Load javascript as preload

I have application in React and I use React from CDN.

When I set standard script with CDN all works.

I'd like force on browser to get scripts earlier.

<link rel="preload" href="http://ift.tt/2tmBuNG" as="script" crossorigin="anonymous" />
    <link rel="preload" href="http://ift.tt/2sCSBxN" as="script" crossorigin="anonymous" />

but when I use this manner than is error that React doesn't exists.

Does exists any way to force on browser to get libraries as soon as possible and provide for my library?

Because this libraries are download (I see in inspector) but react app can't detect it. It looks like browser doesn't treat this files as scripts.