&gt; Client side decorations give way more space to the actual content than to waste space for an almost empty titlebar.<p>If Gnome 3 wanted to fix that, it should just replace its space-wasting default theme. And in reality it&#x27;s a non-issue everywhere else. No other desktop environment even has this debate.<p>&gt; Very strong language but you don&#x27;t explain _at all_!<p>Very easy: Consistency. Look at how absolutely, utterly <i>shit</i> Windows looks nowadays. Word doesn&#x27;t blend in with Explorer doesn&#x27;t blend in with regedit doesn&#x27;t blend it with (the still XP-themed) GPO editor doesn&#x27;t blend in with the new settings app doesn&#x27;t blend in with the control panel doesn&#x27;t blend in with Edge …<p>My window manager should dictate how windows looks. This works for all toolkits, from GTK2 over FLTK over Qt all the way to Mono&#x27;s GDI. All, except GTK3.<p>And yet, it does not have to be a problem! A few years ago, this would have been a no-brainer: When GTK was presented with behavioural differences between desktop environments, it was implemented as a run-time option, configured by the GTK theme to allow desktops to configure GTK to its needs (like &quot;images on buttons&quot;, mandatory in Xfce, shunned in Gnome).<p>Client-side decorations are a compile-time switch. What the hell.<p>&gt; Regarding mouse wheel support: What basis do you say that 1) it was removed 2) it was made out of spite?<p>GTK&#x27;s notebook widget. It was removed for no reason, and users were told to just reimplement it in all applications they needed it in. What the hell.