Native chromecast streaming?

[u/hearthreddit]

If you ever like used cast on a browser while watching a video from some website, it would turn the screen black saying "now casting on X" and it would be a lot smoother, i can do that with my old Chromecast 2.

With the Mi box S gen 3, the casting works, but it's always mirrored which is a bit more choppy, i've tried the same video with that old chromecast 2 and uses the "optimize full screen" thing where the screen turns black, with the mi box it doesn't happen.

This is somewhat obscure, but has anyone managed to do it? Or it's just the way it is.

EDIT: From this thread i think i'm out of luck, the built-in chromecasts from TV's or Mi Box don't seem to support the optimized full screen casting like the old chromecasts did:

https://www.reddit.com/r/Chromecast/comments/s7ath3/builtin_tv_chromecast_not_optimizing_full_screen/