@andrew84 Thanks for the reply. Well, if these are tests of a new player by YouTube itself, then there's nothing we can do about it.

@leocg

Before, the video player looked like this:

Besides the poorly designed volume button, the new player also lags, when the player interface is visible.

For some reason, the video player on YouTube has changed in Opera, while other browsers still use the old player. What could be the reason for this, and how can I switch it back?