I use my ipad with a trackpad a lot, and often with stage manager on an external display. Youtube doesn't play well with that set up. Oddly it'll switch which background color to show (like from dark to light) and as a result the text can get unreadable because the text doesn't always switch with it. The chat/info panes sometimes won't work when you click on them. I've had it not let me click the share button because the share button wouldn't load.

And, yes, Stage Manager is somewhat a niche use case, I suppose. But this isn't a mom and pop app dev. It's google.

Even out of Stage Manager, they don't support the cursor targets like apps are supposed to (maybe they are just using one build and shipping everywhere and hoping for the best). PiP sometimes doesn't work well, and you have to kill the app and restart.

They should do better with one of their flagship apps, is all I'm saying. And Apple, honestly, should do better on their end with stuff like this. They don't even have all native apps built for the Vision Pro that comes out in a couple weeks. It's like, you're the most profitable company on the planet and you don't even bother. It's crazy.