UPDATE: this happened for me only once and then disappeared, so YouTube may have leaked it by mistake.
YouTube has already moved its comments in phones, and now it’s doing the same thing on desktop as you can see in these photos:


While the old comment section is still available, opening the new comment section will make the old comment section disappears:


This may take some time to be applied to everyone as you can see here (Shot at the same time as those):

That same change happened in phones back in 2020, and now they did the same to desktops.
I think this is a huge change for me as now I can see the comments while watching videos, some people may not like this change as they are more familiar with the old way.
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