Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
No, I just tried and it doesn’t work. I tried using two different browser windows then Twitch in Safari and YT in the app. No bueno. If you mute one of the videos you can play two videos at the same time with audio from one, but right now you can’t listen to two things at the same time (at least not those two).
 
This is a thing that really annoys me for years and it’s one of those little things that still make me think the iPad can’t replace a full computer yet.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.