[kps]

> - Tabs.

Should have been a generic window manager feature.

[phkahler]

Apparently Cosmic will even let you combine different apps in the same tab group. I read that but haven't confirmed.

Web browsers had to innovate because OSes, DEs and GUI toolkits stagnated. Tabs and better sandboxing came from web the browser.

[garaetjjte]

BeOS sort-of did that.

[evandrofisico]

fluxbox have been doing that for over 20 years