The latter, unfortunately. Every time you try to access the ad-free video link, there's a chance YouTube will return an error.

When you AirPlay a video, Safari is basically telling the TV, "here's the link to the video, now play it." Then the TV tries to access the link and encounters an error.

This is how I changed my first button to Brave:

yes, just open the Lucky app and go to Search Shortcuts

Yeah. When you buy a game, you're spending money for a good time. When you buy an app, you're spending money for… efficiency and better productivity?

"A good time" is a lot easier to sell than the productivity thingy.

Wow they really don't have any original ideas

Not a dumb question! The quality switcher isn't in theater mode because it would be too close to the fullscreen/PiP buttons. It would fade in and out at different times compared to the native buttons, which would look awkward.

(I couldn't fully replicate the native buttons' fade-in/out behavior 😬)

It's a Safari bug (bugs.webkit.org/show_bug.cgi...). You can try turning on Advanced playback mode to workaround the issue.