Evince lost resize handles

[ExecutorElassus]

lately, I've been noticing my gtk3 (?) applications are gradually taking on a different-looking theme than the one installed. It's nice-looking (relatively minimal, dark blacks and grays), but this last week evince switched over to a different look, and part of it bugs me.

Everything has now been moved into a single titlebar, which looks nice and all (it matches the look the open-file dialog has had for a couple months), but now, there are no resize handles anywhere. This is super-annoying, as I very often have to resize pdf windows to view several simultaneously.

So: evince obviously isn't using the theme I've specified using lxappearance; how do I find out which theme/engine it is using? then:
how do I force this theme to have resize handles, always, so that I can resize windows?

Cheers,

EE

[haarp]

It's all part of Gnome's war on useful interfaces. I'm using Xfce and Gnome apps start looking really weird and lose even more UI elements, one by one. I'd like to fix this aswell.