Bit confused. Since it's a *.js name, I was expecting a library (preferably with source hosted somewhere like GitHub), but it seems more like a hosted solution to me. I created an account and watched up to about 5:00 of the video, but still slightly confused. A better readme perhaps?

Yes definitely, from the page, without looking the video it's hard to tell what is this about at all? Why would I sign up?

    For later offline use, 
    please install Unknown.
    Error loading elmstreet contact support 
    RTFM ლ(ಠ益ಠლ)

I have not found the "fucking manual"

Although this doesn't explicitly relate to your product, it would be better to have duskjs.com as an Alias of ss15-fliptables.divshot.io rather than just redirecting to it. Getting redirected to such a weird website name feels a bit Phishy.

Agree, and would naturally need a new SSL cert for duskjs.com if they want to keep the encryption.

At least they have a sense of humor about themselves:

  request.onsuccess = function(event) {
    // I HAVE NO IDEA WHAT I'M DOING!
    delete request.result.current;
    resolve(request.result);
  };

You should come up with a solution that doesn't require HTTPS. Offline single-page apps are perhaps the only case where people shouldn't care about HTTPS.

Related: http://cloudwall.me/