How to handle injected CSS and JS inside of head about coach HOT 1 OPEN

@tobli and me discussed this offline. As we know there's no way to get the source code from the browser (let us know if you know a way) so we need to do another request to fetch it.

We want to make sure we fetch the HTML in the same session (so we will come in the same "bucket" for optimizely etc so we need to make the request from the browser when we run the javascript to collect the DOM advice. We could fetch the URL using the fetch API (setting the user agent will work right, I tested and it looked ok). What's missing from doing that today, is that the DOM scripts doesn't know anything about the run (they have no configuration = don't know if we are testing as mobile or desktop).

from coach.