You need to follow redirects then, you can do that by passing the option follow_redirect: true, max_redirect: 20 for whatever values you want. Or follow them manually.

I’m not sure why there would be a point to use a headless browser, should just use HTTPoison.

My only suggestion is that as long as you’re using a headless browser you’ll never know what is actually happening. You need to download the document in a regular browser, then look at the network activity in your browser’s dev tools to see what actually happened in terms of redirects etc, then use an HTTP client lib (HTTPoison is the usual choice) to follow the same path.

It’s perfectly possibly that the site you’re hitting uses a combination of redirects AND cookies. Advertising & tracking sometimes complicate the heck out of things. I’ve seen a single page load result in a series of 8 redirects each of which added some damned tracking/advertising info until the request was finally answered.

Uh… that’s a server bug, like big-time server bug… o.O

Well HTTPoison is the thing for that, plus processing the HTML through Meeseeks or something if you need to do that.