I think this was just changed. I noticed they added Mobile Deep Links to the API so I am wondering if this has something to do with that. I cannot image that this was an intentional change to the mobile embed. Why have the option to embed if they just want to redirect your back to Twitch.
We need to find a way to force the URL to think it’s a desktop, but the problem with that is, since it is an embed code, the redirect happens on Twitch’s end based on the window width. I am not sure if there is anything we can do about that.