As someone who thinks browser UI peaked in 2008, Zen just feels like Firefox UI designers on ritalin. Had to about:config hack it to show the KDE system titlebar. This software is not for me.
Since a couple of the machines I use regularly have small screens (12-13”), hiding the standard titlebar and collapsing browser UI elements into the titlebar area were among the userChrome mods I had been applying to Firefox, so that particular bit of UI design in Zen is desirable for me.
On desk-bound machines hooked to 27” displays, this isn’t really necessary, but the UI being built around vertical tabs as the standard (as opposed to most browsers, where vertical tabs are a tacked-on afterthought if they’re even supported without addons) is still a relevant selling point.
