The feature those provide isn't immediately obvious in a static screenshot, the tabs are "magnetic" and you can take your "word" application and "stick" it's tab next to your email tab, and now you have a "tabbed application" with the email app tab on the left, and the word app tab on the right. You might have one "window" that is your front end dev workflow (firefox, vscode, 2-3 term windows) with 5 tabs, and then a second window that is your backend workflow of vscode + 4 terminal tabs, and a database workflow that is pgadmin + 2 terminal tabs. For example. I haven't seen anything like it, and I'm not sure how it handles windows with a smaller fixed window size, like winamp.
> I haven't seen anything like it
I remember using the fluxbox wm like this back on the university Sun machines
It would just stack the windows of different sizes, so if you hit the Winamp tab the smaller Winamp tab would be at the top of the stack. Pretty simple and intuitive.
I loved the tabs on BeOS.
Haiku made them magnetic. In classic BeOS you had to manually position the windows on top of each other, then hold shift and manually drag the tab over from the left. And they wouldn't be tethered together: moving one window wouldn't move the other. It was annoying enough that I never bothered. By the end of BeOS's life I was mostly using the Mac OS 8 titlebar style (accessed by holding down all the modifier keys and pressing the Be menu).