Another vote for being able to disable this. This makes sense on mobile, but if I wanted to keep browsing Twitch while watching a stream, I’d just open another tab. If I use my back button to leave a page, it means I’m done with that page. In other words, I don’t want the video to keep playing in the background.
What’s next? Keeping a stream playing when I back button out of twitch.tv all together? Kappa