What happened at YouTube?

YouTube window has totally changed, …

https://www.theverge.com/2017/8/29/16216868/new-youtube-logo-redesign-font-color-app-design
https://youtube.googleblog.com/2017/08/a-new-youtube-look-that-works-for-you.html
Figured it out, sort of.

(I have two gmail acc’t) I’ve since noticed that in one of them the page layout is fine, same as always.
Video takes up 2/3 column space, right 1/3 is a column of suggested videos and under the video is the comments section.
It’s still there as always.
But when I’m signed in under my second acc’t the video takes up the full frame and under that are video suggestions.
Comments section is missing all together. I don’t know if it’s some setting change -
but I sure didn’t do anything deliberate to change it and suddenly today it flips.
Does that make any sense?
Anyone else experience something like it?

Ah ha, figured it out. When signed in under one account making the page narrow, simply makes the page view narrow and you can scroll left and right.
In the other account, if you make your page too narrow, the comment’s disappears, the 1/3 right column disappears, and video suggestions take up full width.
Widen the page and it pops back into place.